Compare 21/42 and 30/36, Which fraction is greater?

Compare 21/42 and 30/36

21/42 is smaller than 30/36

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 36 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 42 × 6 = 252,
21/42 = 21 × 6/42 × 6 = 126/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
30/36 = 30 × 7/36 × 7 = 210/252
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
126/252 < 210/252 or 21/42 < 30/36

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