Compare 8/12 and 90/21, Which fraction is greater?

Compare 8/12 and 90/21

1^st number: 8/12, 2^nd number: 4 6/21

8/12 is smaller than 90/21

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
8/12 = 8 × 7/12 × 7 = 56/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
56/84 < 360/84 or 8/12 < 90/21

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