Page 116 - Start Up Mathematics_4

Finding Fraction of a Number

To find the fraction of a number, we first divide the number by the denominator of the
fraction, then we multiply the quotient obtained by the numerator.

2
Example 16: Sameer had 12 chocolates. He ate 3 of the chocolates. How many chocolates
did Sameer eat?
2
Solution: Sameer ate of the chocolates. This means he ate 2 out of 3 equal parts of
3
the chocolates.
So, we divide 12 chocolates into 3 equal parts. 12 ÷ 3 = 4
Each part has 4 chocolates.

= + +

2 parts means 2 × 4 = 8 chocolates.

2 2
Thus, we can say that of 12 = × 12 = 8
3 3
So, Sameer ate 8 chocolates.

1
Example 17: Minti bought a pizza which was cut into 6 slices. She ate of the pizza slices
3
and kept the rest to eat later. How many slices of pizza did Minti eat?
1 1
Solution: The pizza had 6 slices. Minti ate of the slices. × 6 = 2
3 3
Thus, Minti ate 2 slices of the pizza.

A Challenge!
1
Quick Tip 1. What is of an hour in
2
minutes?
You can find the fraction of a number by:
2. How many months are
(i) multiplying the number by the numerator.
2
(ii) dividing the product by the denominator. there in of a year?
3

3
Example 18: Find of 20.
4
Solution: Step 1: Divide 20 by 4. (20 ÷ 4 = 5) Quotient = 5

Step 2: Multiply 5 by 3. (5 × 3 = 15)
3 3
So, of 20 = × 20 = 15.
4 4

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