Subject: fractions

which of the following pairs of fractions are equivalent?
questions a-f

(a) 1/5 and 6/30
(b) 4/9 and 16/27
(c) 6/10 and 30/50
(d) 15/20 and 48/64
(e) 2/3 and 33/100
(f) 12/32 and 3/16


please show how u got the answer thank you.

Hi,

To directly compare two fractions you need them to have the same denominator. The challenge here is, for each pair of fractions, find a pair of equivalent fractions with the same denominators and then compare.

(a)

Here the denominators are 5 and 30. Since 30 is 5 times 6, if you multiply the numerator and denominator of the first fraction by 6 you get an equivalent fraction with 30 as its denominator. That is

 1/5 = 1x6/5x6 = 6/30 Thus the first fraction, 1/5 and the second fraction  6/30 are equivalent.

(d)

Here the denominators are 20 and 64 and you need to find a common denominator. Write 20 and 64 in terms of their prime factors.

20 = 22 x 5

64 = 26

Thus a common denominator is 26 x 5 = 320.

 15/20 = 15x16/20x16 = 240/320

and

 48/64 = 48x5/64x5 = 240/320

Hence  15/20 and  48/64 are equivalent.

Cheers,
Penny
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