Compare 21/12 and 5/45, Which fraction is greater?

Compare 21/12 and 5/45

1^st number: 1 9/12, 2^nd number: 5/45

21/12 is greater than 5/45

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 45 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 12 × 15 = 180,
21/12 = 21 × 15/12 × 15 = 315/180
Likewise, for the 2nd fraction, since 45 × 4 = 180,
5/45 = 5 × 4/45 × 4 = 20/180
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
315/180 > 20/180 or 21/12 > 5/45

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