Compare 18/84 and 21/30, Which fraction is greater?

Compare 18/84 and 21/30

18/84 is smaller than 21/30

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 30 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
18/84 = 18 × 5/84 × 5 = 90/420
Likewise, for the 2nd fraction, since 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
90/420 < 294/420 or 18/84 < 21/30

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