Compare 15/80 and 24/21, Which fraction is greater?

Compare 15/80 and 24/21

1^st number: 15/80, 2^nd number: 1 3/21

15/80 is smaller than 24/21

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 80 × 21 = 1680,
15/80 = 15 × 21/80 × 21 = 315/1680
Likewise, for the 2nd fraction, since 21 × 80 = 1680,
24/21 = 24 × 80/21 × 80 = 1920/1680
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
315/1680 < 1920/1680 or 15/80 < 24/21

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