Compare 28/45 and 21/20, Which fraction is greater?

Compare 28/45 and 21/20

1^st number: 28/45, 2^nd number: 1 1/20

28/45 is smaller than 21/20

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 45 × 4 = 180,
28/45 = 28 × 4/45 × 4 = 112/180
Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
112/180 < 189/180 or 28/45 < 21/20

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