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\\November 22, 2023 3:12 PM Surender Prajapati Proof 5 Reader _________________________ Date: ___________________74

1
example 2: Narayan goes for a morning walk every day. If he spends hour each day on
it, how many hours will he spend in a week? 3
1
Solution: Since Narayan spends hour on morning walk every day.
3
1
7
1
Therefore, in a week he will spend 7 × = 7 × 1 = = 2 hours.
3 3 3 3
1
Thus, Narayan will spend 2 hours on morning walk in a week.
3
3
example 3: Siya purchased 5 kg of mangoes for `32 per kg. How much did she pay for
4
them?
Solution: Cost of 1 kg of mangoes = `32
3 23
Weight of mangoes purchased = 5 kg = kg
4 4
3
Amount paid by Siya for 5 kg of mangoes
4

= ` 32 × 23 = ` 32 × 23 = `(8 × 23) = `184
4 4
3
Thus, Siya paid `184 for 5 kg of mangoes.
4

Multiplication of a Fraction by another Fraction

To multiply two or more fractions, multiply their numerators and denominators separately,
to get the numerator and the denominator of product, respectively.

Product of two fractions = Product of numerators
Product of denominators
example 4: Multiply the following.

4
3
3
2
(a) × (b) × × 6
5 7 4 9 20
Solution: 1 1 2
3
4
3
2
(a) × = 3 × 2 = 6 (b) × × 6 = 3 × 4 × 6 = 1 × 1 × 2 = 2 = 1
5 7 5 × 7 35 4 9 20 4 × 9 3 1 × 20 1 × 1 × 20 20 10
1
3
example 5: A painter uses L of paint to colour 1 m of wall. How much paint does he
5
need to colour 2 1 m of wall?
4
3
3
Solution: We have, × 2 1 = × 2 × 4 + 1
5 4 5 4
9
3
= × = 3 × 9 = 27 = 1 7 L
5 4 5 × 4 20 20
Thus, the painter needs 1 7 L of paint to colour 2 1 m of wall.
20 4

94 Mathematics-5