Compare 20/81 and 84/42, Which fraction is greater?

Compare 20/81 and 84/42

1^st number: 20/81, 2^nd number: 2 0/42

20/81 is smaller than 84/42

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 42 is 1134

Next, find the equivalent fraction of both fractional numbers with denominator 1134
For the 1st fraction, since 81 × 14 = 1134,
20/81 = 20 × 14/81 × 14 = 280/1134
Likewise, for the 2nd fraction, since 42 × 27 = 1134,
84/42 = 84 × 27/42 × 27 = 2268/1134
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
280/1134 < 2268/1134 or 20/81 < 84/42

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