BasicOperations
on Fraction
“
A man is like a fraction whose
numerator is what he is and whose
denominator is what he thinks of
himself. The larger the denominator,
the smaller the fraction.
-Leo Tolstoy
WHAT IS A
FRACTION?
Basic things about a fraction…
×A fraction represents a part of a whole. It
consists of a numerator and a denominator.
×The numerator is the number above the line; the
denominator is the number below the line. This
line is called the vinculum which indicates
division.
×Common fractions are also called vulgar
fractions. There are three types of common
fractions. These are proper fractions, improper
fractions, and mixed numbers.
Basic things about a fraction…
×Proper fractions are fractions that express
amounts which are less than a unit. As such, the
numerator is always less than the denominator.
×Improper fractions are fractions that express
amounts which are equal to or greater than a
unit. Hence, the numerator is either equal to or
greater than the denominator.
×Mixed numbers are numbers that consist of a
whole number and a fraction.
Basic things about a fraction…
×You can multiply, divide, add and subtract
fractions
×A common factor is a number that both
denominators are evenly divisible by
×A common denominator is a number that both
denominators share a factor with
Adding and Subtracting Fractions
Get a common Keep the same
denominator denominator
8 3 11
+ =
12 12
2 1 8 3 8 3 11
+ = + + =
3 4 12 12 12 12 12
Add or subtract
the numerators
Multiplying Fractions
Process 1 Process 2
Multiply across, then Reduce early, then
reduce. multiply across.
1 1
3 2 6 1 3 2 1
× = = × =
8 3 24 4 8 4 31 4
Dividing Fractions
9 3
Rewrite as multiplication problem: ÷ =
16 4
Keep the first Flip the second Change division to
fraction. fraction (reciprocate). multiplication.
9 3 9 4 36 3
÷ = × = =
16 4 16 3 48 4
Application
Word Problem
Solving
Nang Lydia Macaya has a total of 125 cavans
of a new strain of pest resistant, high yielding,
locally adapted rice. She plans to distribute them to
4 communities in Panay. If she gives 1/5 of them to
the first community, and the rest divided equally to
3 other communities, how much will each of the last
3 communities get?
A tribe in the province of Compostela Valley
wants to fence a land measuring 78 3/5 meters on
one side, 63 7/10 meters on the second side, 132 5/9
meters on the third side, and 130 1/4 meters on the
fourth side. If they have 2 rolls of 500 meters per
roll of barbed wire at hand, how many more meters
of barbed wire would they
need if they want to fence
the land four times?
Jenel, 8 years old, walks almost 2 hours a day,
hiking uphill and downhill, crossing streams and
walking under the heat of the sun, to reach school
which is approximately 9 5/8 miles away. This
morning, he started walking at 5:30am. At 6:30am,
the school was still 5 1/3 miles away. How far did
Jenel walk so far?
According to the Philippine Statistics
Authority (PSA), there are 263 out of 1000 Filipinos
who are believed to be suffering in extreme poverty
in the first semester of the year 2015. If in the same
year, it has been reported that there are
approximately103,821,858 Filipinos, how many of
this number of Filipinos
are in poverty?
The Philippines is basically an agricultural
country which has a total agricultural area of 9
67/
100 million hectares or about 30 percent of the
total land area of the country cultivated by millions
of Filipino farmers. If this land area will be divided
into smaller lands of 1 467/500 hectares each, how
many million farmers will
be given their own land to
cultivate?
Fraction to
Converting
Decimal and Percent
Converting Fraction to Decimal
Method 1: Converting Method 2: Converting
with Proportion by Division
Multiply the Divide the numerator of
denominator of the the fraction by its
fraction by a number denominator until a
that will make it a remainder of zero
multiple of 10, and the appears…
numerator by the same
number…
Method 1 : By Proportion
3 × 25 75
= = 0.75
4 × 25 100
Find a number you can multiply by Write down just the numerator
the denominator of the fraction to and put it in the correct
make it a multiple of 10. decimal place.
2
1 Multiply both numerator and
3
denominator by that number.
Converting Decimal to Percent
× Simply just move the 1. 0.625 = 62.5%
decimal point two (2)
decimal places to the 2. 0.0364 = 3.64%
right to make the
decimal number a 3. 1.028 = 102.8%
percent.
Method 2 : By Division
𝟎. 𝟔𝟐𝟓 Remember to put a
8 5.000 decimal point after the
0 numerator and another
50 one right above it.
48
20
16
40
40
0
Simple Exercise
Simple Exercise
1. I bought my coat in the 2. There are 36
January sales with 1/3 carpenters in a crew.
off the original price. On a certain day, 29
What percentage was were present. What
taken off the price of percent showed up for
the coat? work? (round to the
nearest tenth)
Simple Exercise
3. When Rani was buying 4. A metal bar weighs
her flat she had to put 8.15 ounces. 93% of
down a deposit of 1/10 the bar is silver. How
of the value of the flat. many ounces of silver
What percentage was are in the bar? (round
this? to the nearest
thousandth)
END OF
SLIDE
