Compare 16/81 and 21/8, Which fraction is greater?

Compare 16/81 and 21/8

1^st number: 16/81, 2^nd number: 2 5/8

16/81 is smaller than 21/8

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 8 is 648

Next, find the equivalent fraction of both fractional numbers with denominator 648
For the 1st fraction, since 81 × 8 = 648,
16/81 = 16 × 8/81 × 8 = 128/648
Likewise, for the 2nd fraction, since 8 × 81 = 648,
21/8 = 21 × 81/8 × 81 = 1701/648
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
128/648 < 1701/648 or 16/81 < 21/8

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