Compare 7/21 and 42/20, Which fraction is greater?

Compare 7/21 and 42/20

1^st number: 7/21, 2^nd number: 2 2/20

7/21 is smaller than 42/20

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
7/21 = 7 × 20/21 × 20 = 140/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
42/20 = 42 × 21/20 × 21 = 882/420
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
140/420 < 882/420 or 7/21 < 42/20

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