Compare 12/72 and 21/20, Which fraction is greater?

Compare 12/72 and 21/20

1^st number: 12/72, 2^nd number: 1 1/20

12/72 is smaller than 21/20

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 72 × 5 = 360,
12/72 = 12 × 5/72 × 5 = 60/360
Likewise, for the 2nd fraction, since 20 × 18 = 360,
21/20 = 21 × 18/20 × 18 = 378/360
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
60/360 < 378/360 or 12/72 < 21/20

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