Page 139 - Start Up Mathematics_6

(b) We observe the denominators of the given fractions. Since 10 ÷ 5 = 2, we multiply
2 2 2 × 2
both the numerator and the denominator of by 2. Now, RHS = = 5 × 2
5
5
4
.
= Hence 4 is the correct number.
10
Example 17: Check whether the given fractions are equivalent:

2 6 3 5
(a) , (b) , Try It Out!
7 21 8 9 1
Solution: (a) We have, 2 × 21 = 42 and 7 × 6 = 42 If 2 the students in Varun’s class are
1
Since, 2 × 21 = 7 × 6 boys and 2 the students in Sangeeta’s
class are girls, explain whether the
2 6
∴ and are equivalent fractions. number of boys and girls in each of the
7 21 two classes is same.
(b) We have, 3 × 9 = 27 and 8 × 5 = 40

Since, 3 × 9 ≠ 8 × 5

3 5
∴ and are not equivalent fractions.
8 9
Example 18: Reduce the following fractions to the simplest form:

75 36 7
(a) (b) (c)
20 42 35

75 75 ÷ 5 15 36 36 ÷ 6 6 7 7 ÷ 7 1
Solution: (a) = = (b) = = (c) = =
20 20 ÷ 5 4 42 42 ÷ 6 7 35 35 ÷ 7 5

Example 19: Karan had 30 pencils, Sheelu had 50 pencils and Tanveer had 70 pencils. After
four months, Karan used up 15 pencils, Sheelu used up 25 pencils and Tanveer used

up 35 pencils. What fraction did each child use up? Check if each child has used up
an equal fraction of his/her pencils?

Solution: Total number Number of Fraction of
Name
of pencils pencils used pencils used

15 1
Karan 30 15 =
30 2

25 1
Sheelu 50 25 =
50 2

35 1
Tanveer 70 35 =
70 2

Clearly, all of them have used up equal fraction of their pencils.

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