Compare 18/15 and 4/21, Which fraction is greater?

Compare 18/15 and 4/21

1^st number: 1 3/15, 2^nd number: 4/21

18/15 is greater than 4/21

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
18/15 = 18 × 7/15 × 7 = 126/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
4/21 = 4 × 5/21 × 5 = 20/105
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
126/105 > 20/105 or 18/15 > 4/21

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