Compare 40/42 and 15/12, Which fraction is greater?

Compare 40/42 and 15/12

1^st number: 40/42, 2^nd number: 1 3/12

40/42 is smaller than 15/12

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 42 × 2 = 84,
40/42 = 40 × 2/42 × 2 = 80/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
80/84 < 105/84 or 40/42 < 15/12

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