Compare 1/21 and 15/45, Which fraction is greater?

Compare 1/21 and 15/45

1/21 is smaller than 15/45

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
1/21 = 1 × 15/21 × 15 = 15/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
15/45 = 15 × 7/45 × 7 = 105/315
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
15/315 < 105/315 or 1/21 < 15/45

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