Compare 21/9 and 72/20, Which fraction is greater?

Compare 21/9 and 72/20

1^st number: 2 3/9, 2^nd number: 3 12/20

21/9 is smaller than 72/20

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 20 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 9 × 20 = 180,
21/9 = 21 × 20/9 × 20 = 420/180
Likewise, for the 2nd fraction, since 20 × 9 = 180,
72/20 = 72 × 9/20 × 9 = 648/180
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
420/180 < 648/180 or 21/9 < 72/20

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