Compare 42/72 and 28/21, Which fraction is greater?

Compare 42/72 and 28/21

1^st number: 42/72, 2^nd number: 1 7/21

42/72 is smaller than 28/21

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
42/72 = 42 × 7/72 × 7 = 294/504
Likewise, for the 2nd fraction, since 21 × 24 = 504,
28/21 = 28 × 24/21 × 24 = 672/504
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
294/504 < 672/504 or 42/72 < 28/21

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