Compare 80/72 and 30/21, Which fraction is greater?

Compare 80/72 and 30/21

1^st number: 1 8/72, 2^nd number: 1 9/21

80/72 is smaller than 30/21

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
80/72 = 80 × 7/72 × 7 = 560/504
Likewise, for the 2nd fraction, since 21 × 24 = 504,
30/21 = 30 × 24/21 × 24 = 720/504
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
560/504 < 720/504 or 80/72 < 30/21

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