Page 186 - New Medley 5 Semester 1

Z Z To multiply a mixed fraction with the whole number, convert it into
improper fraction and then multiply.

Multiplying a Fraction by Another Fraction

We know that every whole number can be expressed in a fractional form
2 20 14
like 2 = , 4 = , 7 = , etc.
1 5 2

And we learnt earlier how to multiply a fraction with a whole number.
Now, consider the following multiplication:

×
8 85 40 8 2
× 5 = = = = 2
15 15 15 3 3

8 8 5 8 × 5 40 8 2
Also, × 5 = × = = = = 2
15 15 1 15 × 1 15 3 3

Thus, we can say that
Productof numeratorsoffractions
Fraction × fraction =
Productofdenominatorsoffractiions

Example 10: Find the product of each of the following.

4 5 8 9 1 1
(a) × (b) × (c) 2 ×2
9 12 15 16 3 7
4 5 4 × 5 20 5
Solution: (a) × = = =
9 12 9 × 12 108 27
We can divide the

Alternative Method: numerators and
1
4 5 1 × 5 5 denominators
× = = by same divisor
9 12 3 9 × 3 27 and multiply the

1 3 quotients left in
8 9 8 9 1 × 3 3
(b) × = × = = numerators and
15 16 15 16 5 × 2 10 denominators
5 2
separately.
1 5
1 1 7 15 1 × 5 5
(c) 2 × 2 = × = = = 5
3 7 3 7 1 × 1 1
1 1
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