Compare 10/21 and 42/56, Which fraction is greater?

Compare 10/21 and 42/56

10/21 is smaller than 42/56

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 56 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
10/21 = 10 × 8/21 × 8 = 80/168
Likewise, for the 2nd fraction, since 56 × 3 = 168,
42/56 = 42 × 3/56 × 3 = 126/168
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
80/168 < 126/168 or 10/21 < 42/56

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