Page 185 - New Medley 5 Semester 1

Multiplication of Fractions

Multiplying a Fraction by a Whole Number

We know that multiplication is a process of repeated addition. This is true

for the fraction also.

2
Consider the following multiplication × 3. Let us observe this addition.
5

+ + =

2 2 2 6 1
+ + = or 1 +
5 5 5 5 5

2 2 2 2 + 2 + 2 2 × 3 6 1
Also, + + = = = or 1
5 5 5 5 5 5 5

2 2 × 3 6 1
Hence, × 3 = = = 1
5 5 5 5

Thus, we can say that

Numeratorofthe fraction ×Whole number
Fraction × whole number =
Denominatorofthe fraction

Note: Reduce the result to its simplest term or change it into mixed
fraction, if it is an improper fraction.

Example 9: Multiply the following.

3 5 1
(a) by 4 (b) 12 by (c) 2 by 6
8 9 2

3 3 × 4 12 3 1
Solution: (a) × 4 = = = = 1
8 8 8 2 2

×
5 12 5 60 20 2
(b) 12 × = = = = 6
9 9 9 3 3

1 5 5 × 6 30
(c) 2 × 6 = × 6 = = = 15
2 2 2 2

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