Compare 42/40 and 28/21, Which fraction is greater?

Compare 42/40 and 28/21

1^st number: 1 2/40, 2^nd number: 1 7/21

42/40 is smaller than 28/21

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
42/40 = 42 × 21/40 × 21 = 882/840
Likewise, for the 2nd fraction, since 21 × 40 = 840,
28/21 = 28 × 40/21 × 40 = 1120/840
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
882/840 < 1120/840 or 42/40 < 28/21

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