Compare 42/21 and 20/54, Which fraction is greater?

Compare 42/21 and 20/54

1^st number: 2 0/21, 2^nd number: 20/54

42/21 is greater than 20/54

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 21 × 18 = 378,
42/21 = 42 × 18/21 × 18 = 756/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
20/54 = 20 × 7/54 × 7 = 140/378
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
756/378 > 140/378 or 42/21 > 20/54

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