Demm 109
Demm 109
Equal Groups
9
Animal Jumps
6 12
3 18
0
0
4
8
12
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18
12
6
0
0
8
16
Are there numbers that both the rabbit and the kangaroo will
touch?
5. To reach 48, how many times did the rabbit jump? _______
How many times did the Kangaroo jump to reach the same number?
_______
What did you observe? Share your thoughts.
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Common Multiples
1. Which numbers do both the frog and the squirrel touch? A few
common multiples of 3 and 4 are _____________________________.
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1. Gulabo’s garden has lily flowers. Each lily flower has 3 petals. How
many petals are there in 12 flowers? Show how you found your
answer.
Multiplication statement
Note for Teachers: In this chapter, the focus is on multiplying 1-, 2-, and 3-digit
numbers by 1-digit numbers, with group sizes less than 10. Children should be
encouraged to break down the ‘multiplier (no. of groups)’ into multiples of 10 to
simplify calculations. They can also use strategies like doubling and halving.
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132
Note for Teachers: Encourage learners to identify different ways of finding the
answers. Children can skip count, count in rows and columns and think in terms
of equal groups. The idea is to make children notice arrays as a way of representing
multiplication.
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Note for Teachers: Encourage children to use Diene’s blocks or a ganit mala
to double or half, especially for big numbers. Doubling and halving are useful
strategies to include when teaching multiplication and division. Teacher can
systematically change the numbers to include different digits in the ones place.
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1 2 3 4 5 6 7 8 9 10
10
What do you notice about the numbers shaded in green? Why is this
happening?
1. Share the patterns that you notice in the table.
2. Are the numbers in row 7 the same as the numbers in column
7? In general, are the numbers in a given row the same as the
numbers in the corresponding column? Why does this happen?
3. Is there a row where all answers (products) are even numbers?
Which rows have this property?
4. Is there a row having only odd numbers as products?
5. Are there rows that have both even and odd numbers? What do
you notice? Why is it so?
6. Are there more even numbers in the chart or odd numbers? How
do you know?
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136
137
× 4
10 10 × 4 = 40
8 8 × 4 = 32
72
138
Let Us Solve
a) 34 × 3 b) 75 × 5
c) 46 × 6 d) 50 × 9
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1. A factory has ordered 58 wheels for the small tempos that they
make. Each tempo has 3 wheels.
In how many tempos can they fix the wheels?
Discuss your thinking in each step.
Number of tempos is 58 ÷ 3
30 wheels are needed for 10 tempos. _______wheels are left.
Note for Teachers: The division performed here is by partial quotient method. It is
carried out by taking away groups of 10s, 5s or any other small multiples, which are
easily available to children. Children can choose multiples of their own choice to solve the
problems. Encourage them to gradually shift to taking away 10s and multiples of 10s.
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Let Us Solve
200 bikes with 2 people on each have
______people.
How did you find it?
100 cars with 4 people in each have
100 × 4 people = _______ people.
500 cars with 4 people in each have
______people.
How did you find it?
4 people in each car
What do you
notice about
500 × 4 = _____ 5×4 = _____
multiplying by
100 × 4 = _____ 50 × 4 = _____
multiples
of 100s?
Note for Teachers: Encourage children to work out the answers in different ways. Also
help them notice the relationship between single digit multiplication and multiples of 100s
of the same group size. Expressing the relationship as ‘hundred-times’ is appropriate.
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More Multiplication
8 8 8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8 8 8
100 autorickshaws with
8 passengers each
8 8 8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8 8 8
8 8 8 8 8 8 8 8 8 8
20 autorickshaws with
8 8 8 8 8 8 8 8 8 8 8 passengers each
8 8 8 8 8 8 8 8 8 8
8 8 8 8 8 5 autorickshaws
with 8 passengers each
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Let Us Solve
1. BP Girl’s school has decided to give all its students two pencils on
the first day of school.
It has 465 students.
How many pencils does the school need to buy?
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More Division
9 boats have to ferry 108 people waiting along the banks of the Cauvery
River. Every boat carries the same number of people. How many people
should be ferried in each boat?
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children ______________
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ec
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Using the above way of thinking, solve the following problems.
Observe and explain the patterns that you notice below.
A B C
1. A load carrying truck has 6 tyres. Chippi the lizard sees 60 tyres.
How many trucks are there?
2. Chippi sees 80 wheels in a car parking space. How many cars are
standing in the parking space?
3. Chippi sees 600 legs of ants walking towards the anthill. How
many ants are there?
4. A fancy shop has packed 800 rubber bands in several packets.
Each packet has 4 rubber bands.
How many packets of rubber bands does the shop have?
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147
6. Solve
a) 45 × 9 b) 507 × 7
c) 94 ÷ 4 d) 778 ÷ 6
e) 94 × 5 f) 396 × 4
g) 83 ÷ 3 h) 635 ÷ 5
Note for Teachers: The “always true, never true, or sometimes true” type of
questions in math are designed to help students understand and evaluate the
validity of mathematical statements under different conditions. They encourage
critical thinking, testing conceptual understanding and encouraging students
to reason logically with counter examples. They help students to move beyond
rote memorisation to a better understanding of mathematical principles.
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