Math Magic Class 5 Complete Book
Math Magic Class 5 Complete Book
                                                 2020-21
Who is Monto waiting for?
                   D                          X
 1     2      3     4     5       6      7    8    9    10
       M                                 P              I
 11    12    13    14    15      16      17   18   19   20
                   O
 21 22       23    24    25      26      27   28   29   30
 R                 N              U
 31    32    33    34    35      36      37   38   39   40
                    B W                       S
 41    42    43    44    45      46      47   48   49   50
       J                         H                      E
 51    52    53    54    55      56      57   58   59   60
Mark with a red dot all the numbers which can be divided by 2.
Mark a yellow dot on the numbers which can be divided by 3 and
a blue dot on the numbers which can be divided by 4.
Which are the boxes which have dots of all three colours?
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Meow Game
Make children play this game several times with multiples of different numbers.
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Dice Game
Throw two dice together. What are the
numbers that turn up on the faces of the
dice? Make a two-digit number using them.
If it is a multiple of any of the numbers
written next to the circles, you can write it
in that circle. Then it is your friend’s turn.
The one who can write more numbers in 10
rounds is the winner.
6 4
5 7
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Common Multiples
3 5
                                                                            ite
                                                                    do I wr le
                                                         Where
                                                              I t i s a multip
                                                         15 ?                  .
                                                               b o t h 3 and 5
                                                           of
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Repeat the game by putting the multiples of 4, 6 and 5 in the circles.
  4
                                          6
      5
❈ What common multiples of 5 and 6 did
  you write in the green part?
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More tamarind seeds
Ammini is arranging 12 tamarind seeds in
the form of different rectangles. Try to make
more rectangles like this using 12 tamarind
seeds. How many different rectangles can
you make?
If there are 15 tamarind seeds how many
rectangles can you make?
Colouring the Grid
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❈ What is the length and width of the rectangle you coloured?
❈ In how many ways can you colour a rectangle of 20 boxes?
  Colour them all in the grid, and write the length and width of
  each rectangle you have coloured.
Bangles
There are 18 bangles on
the rod. Meena is trying to
group them. She can put
them in groups of 2, 3, 6, 9
and 18 — without any
bangle being left.
❈ How many groups will
  she have if she makes
  groups of 1 bangle
  each? ____
Now complete the table,               Number      Different groups we can make
for different numbers of             of bangles
bangles. For each number                  18          1, 2, 3, 6, 9, 18
see what different groups
can be made.                              24          1, 2, ...............
                                          5
                                          9
                                          7
                                          2
                                          10
                                          1
                                          20
                                          13
                                          21
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Fill the Chart
Complete the multiplication chart given here.
× 1 2 3 4 5 6 7 8 9 10 11 12
1 12
2 12
3 12 21
4 12 40
5 20
6 12
8 72
10
11 66
12 12
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❈ What are the factors of 10? ___________
                                                       10
  Can you do this from the chart?                      5×2
❈ What are the factors of 36 ? ___________             ___
❈ What is the biggest number for which you can find the factors
  from this chart?
❈ What can you do for numbers bigger than that?
Common factors
Write the factors of 25 in the red circle and the factors of 35 in the
blue circle.
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Factor Tree
Look at the factor tree. Now can you make another tree like this?
                   3       3
                                2
                       9
18 18
❈ In how many ways can you draw a factor tree for 24? Draw
  three of them below.
24 24 24
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               2) Manoj has made a new house. He wants to lay
               tiles on the floor. The size of the room is 9 feet × 12
               feet. In the market, there are three kinds of square
               tiles: 1 foot × 1 foot, 2 feet × 2 feet and 3 feet × 3 feet.
               Which size of tile should he buy for his room, so that
               he can lay it without cutting?
90
                                                                                 90
                              fee
fee
                                                                                   fee
                               t
Road
Rani, Geetha and Naseema live near each other. The distance
from their houses to the road is 90 feet. They decided to tile the
path to the road. They all bought tiles of different designs and
length. Rani bought the shortest tile,Geetha bought the middle
sized one and Naseema bought the longest one. If they could
tile the path without cutting any of the tiles, what is the size of
the tiles each has bought? Suggest 3 different solutions.
Explain how you get this answer.
  It will be useful to have a discussion about a ‘foot’ and how we use it often to talk about our
  own heights. Children can use their cm scale to get idea about how long a foot is.
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  7       Can You See the Pattern?
   Isha, your skirt                     My mother
                                        made this
     is beautiful!
                                         pattern
                                                           I have seen the same
                                                         block making a different
                                                            pattern on a kurta.
Now you use these two rules to make patterns with this block.
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Turns and Patterns
Practice time
a)
         N                                      N
                            N
b)
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c)
d)
      F           F
                  F
a)
                    F
The rule of the pattern is — turning by 45º each time. Which will
be the next? Tick (✓) the right one.
                            F
                                              F
     F
              (   )                                 (   )
                                     (   )
Using the same rule take it forward till you get back to what you
started with.
b)
     L
         L
c)
     P
         P
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3) Some patterns are given below on the left side of the red line.
   For each pattern, write the rule. Then choose what comes
   next from the right side of the line and tick (✓) it.
a)
Rule:
b)
Rule:
c)
Rule:
d)
Rule:
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Look for a Pattern
Mark that picture which is breaking the rule. Also correct it.
a)
b)
c)
d)
Magic Squares
52 47
You can see Math-Magic Class IV (page 11) for similar magic patterns.
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Magic Hexagons
Look at the patterns of numbers in hexagons.
Each side has 2 circles and 1 box.                                               7
                                                                                        70
                                                                         98
   You get the
 number in each                                                14                                     10
box by multiplying
  the numbers in
 the circles next                                              70                                     20
       to it.
                                                               5                                      2
                                                                      65
                                                                                           26
                                                                                13
      5            13       =      65          Look at the number 65 in the box.
                                               Which are the circles next to it?
                            =      70          Can you see how the rule works?
      6                                    7               4                                      8
                                                                    64
                      17
Now you also make your own magic hexagons.
  You can discuss that a hexagon is a six-sided closed figure, but this is not to be evaluated.
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Numbers and Numbers
24 + 19 + 37 = 37 + 24 + 19
a) 14 + + = 34 + 14 + 20
b) + 42 + = 65 + + 80
d)                    +                  +                 =               +                  +
❈ Now, look at this —                   48       ×         13         =           13        ×       48
     Check if it is true or not.
             See it is the
                                                                             Oh, yes! It is
           same forward as
                                                                            1,2,1 from right
           well as backward.
                                                                              to left also!
Discuss with students that changing the order of numbers does not make any difference to the sum.
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Come, let’s               Take a number, say              43
see how to
 get such                 Now turn it back to front 34
 numbers.                                                                 You have
                          Then add them together 77                    reversed the
                                                                         number by
                        77 is one such special number.                 writing it back
                        There are many such numbers.                      to front.
N O L E M O N S N O M E L O N
                    S T E P      N O T        O N        P E T S
Did you notice that it reads the same from both sides — right to
left and left to right?
Now try and use words in a special way.
  Special words/numbers which read the same both ways are called palindromes. Help
  children to read them from both the ends.
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Calendar Magic
Let us mark a 3 × 3 box (9 dates) on the calendar and see some magic.
8 9 10 11 12 13 14
                                                                       Won't that
   15        16        17        18        19         20        21
                                                                       take some
                                                                         time?
   22        23        24        25        26         27        28
                                                                                 The total
   29        30        31                                                         is 99.
Add 8 to it +8
= 11
Multiply it by 9 ×9
Now you choose any 3 × 3 box from a calendar and find the total
in the same way. Play this game with your family.
You can see Math-Magic Class III (page 105 -106 ) for other calendar tricks.
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Some more Number Patterns
❈ Take any number. Now multiply it by 2, 3, 4 ............... at every
  step. Also add 3 to it at each step. Look at the difference in the
  answer. Is it the same at every step?
                  12               2       +         3          =         27
                  12               3       +         3          =         39
                  12               4       +         3          =         51
                  12               5       +         3          =         63
                  12                       +         3          =
                                   7       +         3          =
                                           +         3          =
                                           +                    =
  Now try doing it with some other number and also take a
  different number to add at each step .
❈ Look at the numbers below. Look for the pattern. Can you
  take it forward?
                                (9 – 1) ÷ 8 =                 1
                              (98 – 2) ÷ 8 =                12
                            (987 – 3) ÷ 8 = 123
                          (9876 – 4) ÷ 8 = ____
                        (98765 – 5) ÷ 8 = ____
                    ( ________–__ ) ÷ 8 = ____
                 ( __________–__ ) ÷ 8 = ____
  Encourage children to read aloud the numbers on the left hand side, even if they can not read
  them correctly. Some of the numbers are large. To help children read them, recall the concept
  of 1 lakh or 100 thousand.
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Smart Adding                                                   What if someone
                                                             gives you to add ten
                                                             numbers together?
                          1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 +10 = 55
Oh! I can find
 it quickly.             11+12 +           +      +      +      +     +      +     +20 = 155
                         21 +       +      +      +      +      +     +      +     +30 =
    Smart! How
    can you do           31 +       +      +      +      +      +     +      +     +40 =
      that?
                         41 +       +      +      +      +      +     +      +     +50 =
  I can get the
  sum without            51 +       +      +      +      +      +     +      +     +60 = 555
     adding.
                         61 +       +      +      +      +      +     +      +     +70 =
❈ Did you notice some pattern in the answers?
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Secret Numbers
❈ Write a set of clues for a secret number of your own. Then give
  it to a friend to guess your secret number.
Number Surprises
a) Ask your friend — Write down your age. Add 5 to it. Multiply
   the sum by 2. Subtract 10 from it. Next divide it by 2. What
   do you get?
  Is your friend surprised?
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b)                  Take a number
Double it 2 =
Multiply by 5 5 =
         c)
                         Take a number
Double it 2 =
                         Again double it                  2   =
               Add the number you took
                                                      +       =
                      first to the answer
Divide by 10 ÷ 10 =
1 = 1 × 1
121 = 11 × 11
1234321 = ?
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  8         Mapping Your Way
Ashi is going to India Gate to see the Republic Day Parade with
the other children of her school. As the children settle down, they
hear something about India Gate on the loudspeaker. “To the
right of the President is the India Gate. This was built in memory of the
Indian soldiers who died in the First World War.”
There are lots of people sitting on both sides of Rajpath, the main
road along which the parade passes. Children are talking about
the buildings they can see around them.
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Here is a photograph taken from a helicopter. You can see
Rajpath — the road which joins India Gate to Rashtrapati
Bhawan. Mark where on Rajpath will Aditi be.
                                                                                                     Map 1
Rashtrapati Bhavan
Vijay Chowk
                                                                               Rajpath
                                                           Janpath                       Janpath
                                                                               Rajpath
                                                                                                                      rg
                                                                                                                    Ma
                                                                                                              dhi
                                                      Man Singh Rd                                        Gan
                                                                                                tu  rba
                                                                                            Kas
                                                                                           Tila
                                                                 Rd                             k
                                                            in                                      Ma
                                                          sa                                          rg
                                                      Hus
                                                  kir
                                                Za                     National Stadium
                                          Dr.
1) Have you seen a map of a city? Look at Map 1. Match it with the
   photo and find out where India Gate is. Draw it on the map.
2) Some roads are shown in this part of the map. Look for them in
   the photo.
3) Name roads that you will cross on your way from Rashtrapati
   Bhawan to India Gate.
4) LookfortheNationalStadiuminMap1.Canyouseeitinthephoto?
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The Central Hexagon
If we ‘zoom in’ to look more closely at one part of the map, it looks
like this.
                                                                      Janpath
                                                                                                                          Map 2
Ak
                                                                Rajpath
                                     ba
                                                                                                 Rd
                                      rR
                                                                                             ka
                                          d
                                                                                         ho
                                                                                        As
                        Man Singh Rd                    Man Singh Rd
                    Sh                                                                                               rg
                        ah
                             jah                                                                               i   Ma
                                an                              India
                                                                                                            dh
                                     Rd                                                                 an
                                                                                                 rbaG
                                                                                             stu
                                                                                        Ka
                                                        India             Gate
                          Children's
                              Park                                                       Til
                                            rg                                               a
                                         Ma                                                    kM
                                    a in                                                              arg
                                 ss
                                                      Rd
                              Hu
                          kir                                                Pu
                        Za
                                                   ah
                                                                                 ran
                   Dr
                                                 Sh
                                                                                  aQ
                                              er
                                                                                       ila
                                              Sh
                                                                                        Rd
                                                      National Stadium
Look at the shape of the yellow area. Have you seen this shape
before? How many sides does it have?
This place is called the Central Hexagon.
Find out from the map
1) If you are walking on Rajpath then after India Gate on which
   side would Children’s Park be?
2) Which of these roads make the biggest angle between them?
  a) Man Singh Road and Shahjahan Road
  b) Ashoka Road and Man Singh Road (the angle away from
     India Gate)
  c) Janpath and Rajpath
3) Which of the above pairs of roads cut at right angles?
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           Waiting for the Parade
           While waiting for the parade, Kancha and some of his friends
           wonder where this parade ends. Kancha is carrying a newspaper
           in which the route of the parade is written —
           Vijay Chowk — Rajpath — India Gate — Tilak Marg — B.S. Zafar
           Marg — Subhash Marg — Red Fort.
                                                                 NORTH
                                                                                                                                                                                      Map 3
        The children look at this map
        to see the parade route.                                                          Red Fort
Chandni Chowk Rd
                                                                                   Marg
                                                                                       sh
                                                                                          ha      b
                                                Jama Masjid
                                                                                               Su
                                                                                                      Marg
                                                                                                       Subhash
Raj Ghat
                                                                                                                                                                              Yamuna River
                                                                                                                            Za far Ma rg
Medical College
                                                                                                                                                                                              E AST
W EST
                                             Connaught
                                               Place
                                                                                                          Ba ha du r .Sh ah
Ring Rd
                                                                                                                                     Doll's
                                                                                                                                    Museum
                                                                                                                                                           I.G. Stadium
                                                                                                                                                           Rin
                                                                                                                                                              gR
                                                                                                                                           Pragati
                                                                                                                                                              d
                                                                                            rg
                                                                                          Ma
                                                                                                                                           Maidan
    Rashtrapati
                                                                                           k
                                                                                      Tila
     Bhavan
                                 Rafi Marg
Janpath
                         Vijay
                        Chowk
                                                                                               National
                                                                                                                                                                        Rin
                                                                                               Stadium
                                                                                                                                                                         gR
                                                                                                                                                                          d
                                                                       Rd
Mathura Rd
             11 Murti
                                                                      an
                                                                 jah
                                                                 ah
                                                             Sh
S OUTH Scale: 2 cm = 1 km
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                      Hey! See, that is
                                                           And the long
                    India Gate and this is
                                                           road between
                     Rashtrapati Bhawan.                                          Let's guess how
                                                         these is Rajpath.
                                                                                  many kilometres
                                                                                  long Rajpath is.
     My mother told me it is
     2 km from Vijay Chowk                  On this map, it is about
         to India Gate.                      4 cm. So 4 cm on the
                                              map is the same as                      You are right!
                                             2 km on the ground.                    See, it is written
                                                                                    at the bottom of
                                                                                     this map. Scale:
                                                                                      2 cm = 1 km
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Trip to Red Fort
"When we reached Red Fort, there was a
long queue for tickets. The main entrance
is called Lahori Gate. After entering it,
we turned left into a long corridor with
little shops on both sides. This is called
Meena Bazar. I bought some lovely
bangles from there for my sister".
Moti Mahal
Diwan-e-Khaas
                                                               Diwan-e-Aam
     N ORTH
S OUTH
Meena Bazar
Lahori Gate
                                                                        Subhash Marg
                                                   W EST
     Scale: 1 cm = 100 m
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                                                  "You can go straight through Naqqar
  Naqqar Khana —
  where drums were                                Khana and reach Diwan-e-Aam. This
beaten to shout out the
   king's messages                                is where the king used to meet the
                                                  common people.
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Make It Bigger, Make It Smaller.
  2 cm
   grid
The side of the square was made two times bigger. Does its area
also become two times bigger?
   Enlarging or reducing of pictures and maps can be done on the classroom floor, the mud ground
   etc. This should be related to the use of scale in maps, which keeps the shape the same.
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Now try this —
This is a part of the parade-route Map 3.
1)   Can you see which part of the route-
     map it is?
2)   Now try to make it bigger in this 2 cm            1 cm grid
     grid. Remember that the ‘shape’ of
     the map should not change.
3)   If the parade route map is smaller,
     and the distance between India Gate
     and Vijay Chowk becomes 2 cm,
     what would be its scale?
     ●   1 cm on map = 1 km on ground
         1
     ●   2 cm on map = 1 km on ground
     ●   2 cm on map = 1 km on ground
                                                         2 cm grid
Dancers from Different States
The children saw many floats (jhankis) and dancers in the parade.
Dancers from
  Karnataka
were the best.
                                            I liked the Tripura dance. From
                 All these people have      Tripura and Sikkim they have to
                 to travel so much to         travel far, but Haryana and
                     come to Delhi!         Uttarakhand are closer to Delhi.
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Look at the map of India below and find the states these children
are talking about. Answer the questions:
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2) Jammu and Kashmir is to the north of Delhi so the team
   from there travels towards south to reach Delhi. Which
   states does it cross?
3) Nonu lives in Gujarat. Nonu's friend Javed lives in West Bengal.
   Nonu wants to visit his friend. In which direction will he travel?
  a)   Towards west
  b)   Towards east
  c)   Towards south
  d)   Towards north
4) Is there any state which is to the north of Jammu and Kashmir?
5) Is there any state which is to the west of Gujarat?
6) If 1 cm on the map shows 200 km on the ground, use this
   scale to find out:
  A) About how far is Delhi from Jaipur?
  a) 50 km          b) 500 km            c) 250 km
  B) Estimate, how far is Jaipur from Bhopal?
  On the map = _______ cm.
  On the ground = _______ km.
7) Look at the map and tell:
  a) Which state is surrounded by four other states?
  b) Which state has the largest area? If its name is not in the
     map, find it from your teacher or parents.
       Explain how you got your answer.
  c) Which state is about 8 times bigger in area than Sikkim?
       ●   Uttar Pradesh
       ●   Tripura
       ●   Maharashtra
       ●   Himachal Pradesh
  d) About how many times of Punjab is the area of Rajasthan?
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The Sea
Bala is standing on the sea-coast and looking at the vast sea. The
sea looks endless .
Have you seen the sea? In the picture where is the sea? Now look for
the sea in the map of India. What colour is used to show the sea?
Find out
Look for different maps. Compare the different scales used in a
local area map, a map of India and a world map etc.
Lines between the States
Sabu is confused about the lines shown between the states.
                               I travelled from Delhi to Haryana, but
                                I never saw any lines on the ground.
                                  How do we see them on the map?
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 Distances between Towns                                                         Map 6
                                                                                              Bhelpur
 These are five towns. Find out:
                                                                                               Dhoklabad
 1) How many cm away is Idlipur                                             Chholaghat
                                                                                    Hall
                             Garden
Assembly Ground
                                       Window
Scale: 2 cm = 5 m
III A V II IX VII VI A
Door
III B IV I X VIII VI B
                                              Playground
                    Office                                                 Main Gate
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1) How many times bigger is the area of the Assembly ground than
   that of the office?
2) How much is the length and width of each classroom?
  a) length 5 m, width 4 m                         b) length 2 m, width 1 m
  c) length 12 m, width 10 m                       d) length 5 m, width 5 m
3) All the classrooms in Ashi’s school look like this.
                                      Blackboard             Map 8
         Window                                               Door
                            Benches
                                                              Notice board
         Window
                  Almirah
Display board
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  9            Boxes and Sketches
Sweet Box
Ramya went to buy sweets. The shopkeeper took a paper cut-out
and quickly made a lovely pink box for the sweets!
a) c)
b) d)
  This chapter focuses on visualisation of 3-dimensional shapes and how they can be
  represented on paper (in 2 dimensions). The representation used here are nets (like the
  ones above), layout plans for a house, and perspective drawings.
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Shapes that Fold into a Cube
A. Buddha wants to make a paper
   cube using a squared sheet. He
   knows that all the faces of a
                                       How many faces
   cube are squares.
                                        does the cube
                                        have? _____
He draws two different shapes.
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            I can make
            open boxes
             with both
              these.
                                                               But with these
                                                               I cannot make
                                                                open boxes.
❈ Find out which of the other 8 shapes (on page 46) can be folded
  to make an open box.
❈ Draw more shapes which will not fold to make an open box.
Boxes and Boxes
All boxes are not cubes. Here are some different kinds of boxes.
Match the shape on the left with a box into which it will fold.
  Making mental images of shapes is an important mathematical ability. Children will need
  many exercises to visualise the net of a box, to think of how it looks when flattened, and also
  to check which nets (like those on page 126) do not make a box.
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Floor Maps
                                Window
                                                For making a house a floor map
      Window                                    is first made. Have you ever
                                                seen a floor map? Here is a floor
                                                map of Vibha’s house. It shows
                                                where the windows and the
                       Door
                                Window          doors are in the house.
         Window
❈ Which is the front side of her house? How many windows are
  there on the front side?
     d)                          c)
❈ Why do the other three deep drawings not match the floor
  map? Discuss.
  A 3-dimensional perspective drawing has been called a 'deep drawing' so that children get a
  sense of the need to represent depth. They should be able to see the difference between
  deep drawings and layout plans.
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Practice time
1. Look at this floor map of a house. Make doors and windows on
   the deep drawing of this house.
Window Window
  Door
           Window                   Window
a) b)
 c)             d)                 e)          f)    g)
  ❈ Which of the drawings look correct to you? Discuss.
  ❈ Can you add some lines to make drawing f ) into a deep
    drawing of the cube?
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Puzzle
This cut-out is folded to make a cube.
a) b) c) d) e)
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Matchbox Play
Navin, Bhaskar and Pratigya made this bridge using matchboxes.
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❈ If you look at the bridge from the top, how will it look? Choose
  the right drawing below:
              a)
b)
❈ Look at the photo and try to make a deep drawing of this bridge.
Practice time
1) Make drawings to show how this bridge will look
     ❈ From the top
     ❈ From the front
a) b) c) d)
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             11          Area and its Boundary
11 cm
3 cm
Piece B
                                  2020-21
❈ Altogether how many squares can be arranged on it? ________
Piece A
25 Hkkjr India
  Encourage children to first discuss different strategies for comparing the area of things by
  using different tokens, stamps, etc. In Class IV they have compared irregular shapes by
  counting squares. In the case of rectangles they can measure the sides to see how many
  squares of 1 cm side will fit in the whole shape.
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Check your guess
a) Measure the yellow rectangle. It is ________ cm long.
Practice time
a) Arbaz plans to tile his kitchen floor with
   green square tiles. Each side of the tile is 10
   cm. His kitchen is 220 cm in length and 180
   cm wide. How many tiles will he need?
   This ‘Guess and check’ activity can be done in the class by making use of other things
   present. For example: how many postcards can be placed on the top of the mathematics
   book, how many charts will cover the classroom walls, etc? Children can be asked to check
   their guesses by tiling things wherever possible. Once they are able to make close guesses,
   this work can be further extended by asking them to guess the area in terms of square cm.
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d) A square carrom board has a perimeter of 320 cm.
   How much is its area?
e) How many tiles like the triangle given here will fit
   in the white design?
This triangle      Area of design = ________ square cm
is half of the
  cm square
My Belt is Longest!
Take a thick paper sheet of length 14 cm and width 9 cm. You
can also use an old postcard.
❈ What is its area? What is its perimeter?
❈ Now cut strips of equal sizes out of it.
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Using tape join the strips, end to
end, to make a belt.
❈ How long is your belt?_____
❈ What is its perimeter _____
❈ Whose belt is the longest in the
  class? _____
Discuss
❈ Why did some of your friends get longer belts than others?
❈ Is the area of your belt the same as the area of the postcard?
  Why or why not?
❈ What will you do to get a longer belt next time?
  The aim of the belt activity is to understand that things with the same area can take different
  forms and also have very different perimeters. While measuring sides, lengths in mm can be
  rounded off for this activity.
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People People Everywhere                        With four Math-Magic
                                                books in a line you can
A) You can play this game in a ground.         get the length of around
                                                   one metre 9 cm.
  Make two squares of one square metre each.
  Divide your class in two teams. Ready to play!
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  Can you imagine how big a
square of side 1 km is! It has
                                                                     In West Bengal there are
an area of ______ square km.
                                                                     about 900 people living in
Guess how many people can live
                                                                           a square km.
           on that.
                                                                      But in Arunachal Pradesh
                                                                     it feels very lonely! There
                                                                       are less than 15 people
                                                                         living in a square km!
 ❈ Can you divide the land equally? Show how you will divide it.
   Remember each person has to get a tree. Colour each person’s
   piece of land differently.
    Children are not expected to do conversion of sq m into sq km or vice-versa. The aim of
    exercise B is to develop a sense of how big or small the units of sq m and sq km are.
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❈ If each square on this page is equal to 1 square
  metre of land, how much land will each of her
  children get? ________ square m
Chumki, Jhumri and Imran need wire to make
a fence.
❈ Who will need the longest wire for fencing? _________
Practice time
A. Look at the table. If you were to write the area of each of these
   which column would you choose? Make a ( ✔).
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     B. Draw a square of 9 square cm. Write A on it.
       Draw another square with double the side.
       Write B on it.
     Answer these —
     1. The perimeter of square A is __________ cm.
     2. The side of square B is __________ cm.
     3. The area of square B is __________ square cm.
     4. The area of square B is __________ times the
        area of square A.
     5. The perimeter of square B is __________ cm.
     6. The perimeter of square B is __________ times the perimeter of
        square A.
1. 2.
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Thread Play
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Save the Birds
There are two beautiful lakes near a village. People come for
boating and picnics in both the lakes. The village Panchayat is
worried that with the noise of the boats the birds will stop
coming. The Panchayat wants motor boats in only one lake. The
other lake will be saved for the birds to make their nests.
A B
                            2020-21
     f) Find the area of lake B on the drawing in square cm. What is its
        actual area in square km?
     King's Story
     The King was very happy with carpenters Cheggu and Anar. They
     had made a very big and beautiful bed for him. So as gifts the
     king wanted to give some land to Cheggu, and some gold to Anar.
          take as
 Cheggu, s what                          Cheggu was happy. He took 100
       nd a
much la thin 100                         metres of wire and tried to make
         i
 comes w f wire.
        s  o                             different rectangles.
  meter
                                         He made a 10 m × 40 m rectangle.
                                         Its area was 400 square metres.
                                         So he next made a 30 m × 20 m
                                         rectangle.
                                         ❈ What is its area? Is it more than
                                           the first rectangle?
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So Anar also tried many different ways to make a
boundary for 800 square metres of land.
❈ He made rectangles A, B and C of different sizes.
  Find out the length of the boundary of each. How
  much gold wire will he get for these rectangles?
A       40 m × 20 m
                          Gold wire for A = _________ metres
C 800 m × 1 m
But then Anar made an even longer rectangle.... See how long!
D
                            8000 m × 0.1 m
So he will get ____________ metres of gold wire!!
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  12      Smart Charts
Chi-Chi, Meow-Meow
Yamini did a project ‘Animals and Birds’. She asked each child of
her class about one favourite pet animal.
                                                    24
                Cats
Dogs
Rabbits
Cows
Parrots
Goats
Squirrel
✤ Look at the tally marks and write the number for each animal
  in the table. How many children in all did Yamini talk to?
' Which is the most favourite pet animal in this table?
✤
'
✤ Which pet will you like to have? What will you name it? Which
  other animals can be kept at home? Discuss.
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Making Tally Marks on the Road
Sumita stood on the road for half an
hour and counted the number of
vehicles passing by. She made a tally
mark for each vehicle. This helped her
in counting quickly the total number
of vehicles in each group.
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                                              Tally Marks                 Number
Cycle
Car
Auto rickshaw
Bus
Cycle rickshaw
Truck
  Children should be encouraged to use tally marks to simultaneously record data of a variety of
  things with larger numbers.
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Helping Hands
In the EVS period, the teacher
asked children whether they
help their parents at home.
There were different answers.
Children named the work in
which they help their parents
the most. The teacher collected
their answers and made a table.
  Washing clothes                      3
  Making, serving food             25
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Now you can fill the chapati chart to show the numbers given in the
table.
1) Look and find out
Children who help in making or serving food are
Playing football
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Ad Mad!!
Ragini loves to watch cartoons on television. One day she
thought of counting the number of ads during the breaks. She
found that in each break there were 14 advertisements. In 10 of
those ads there were children as actors.
                      Try yourself
                  ? ✤ Next time when you watch your favourite
                        TV programme, count the number of
                  '     advertisements during each break. Use
                        tally marks. Put a dot below the tally
                        when you find children in any
                        advertisement.
                      ✤ Compare with your friends. Do you get
                  '     different answers?
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Hot and Cold
                                                                                               Bangalore
                                                       Bangalore
                                                                                                           Jaisalmer
                                                                   Jaisalmer
                                                                                               10°
                                                       Shimla
                                      10°C                                     10°C
                                                                                               Shimla
                                                                                       Delhi
                                              Delhi
1 June 1 December
Try yourself
On any one day, choose any three cities and record their
temperature from the TV or newspaper.
✤ Make a bar chart in your notebook and ask your friends a few
  questions about it. See if they understand your chart!
  Encourage children to look at the map of India to locate different cities. They can try to relate
  the temperature variations in a city to get an idea of the climate there.
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Rabbits in Australia
Earlier there were no rabbits in Australia. Rabbits were brought
to Australia around the year 1780. At that time there were no
animals in Australia which ate rabbits. So the rabbits began to
multiply at a very fast rate. Imagine what they did to the crops!
Start 10
1 year 18
2 year 32
3 year 58
4 year 108
5 year
6 year
a) a little less than double the number of rabbits in the last year.
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    Family Tree
    Madhav went to a wedding along
    with his parents. He met many
    relatives there. But he didn’t know everyone. He met his
    mother’s grandfather, but found that her grandmother is not
    alive. He also found that her Dadi’s mother (grandmother’s
    mother) is still alive, and is more than a hundred years old.
                                                                                                                     Great
                                    Shobna's                                                                     grand parents
                                      Dadi
Shobna's                                                                            Shobna's
                                                    Shobna's                                                     IV Generation
  Dada                                                                                Nani
                                                     Nana
Grand parents
           Shobna's                                                                            Shobna's
            Father                                                                                               III Generation
                                                                                                Mother
                                                                                                                   Madhav's
                                                                                                                   Parents
                Madhav's
                 Father                                              Madhav's Mother
                                                                                                                 II Generation
                                                                         Shobna
Madhav
                      Madhav
                                                                                                                 I Generation
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       Madhav’s mother helped him understand her family with
       the help of this drawing. You can also find out about your
       older generations using such a family tree.
2) How many great, great grand parents in all does Madhav have?
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                                      12
11
                                      10
            Length of plant (in cm)
                                           0     4        8             12     16      20
                                                          Days
Find out from the growth chart
a) Between which days did the length of the plant change the most?
b) What could be the length of this plant on the 14th day? Guess.
c) Will the plant keep growing all the time? What will be its length
   on the 100th day? Make a guess!
  There should be some discussion on the last question. Children should be encouraged to
  observe growth patterns of many other plants and animals.
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