Compare 3/12 and 42/81, Which fraction is greater?

Compare 3/12 and 42/81

3/12 is smaller than 42/81

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 81 is 324

Next, find the equivalent fraction of both fractional numbers with denominator 324
For the 1st fraction, since 12 × 27 = 324,
3/12 = 3 × 27/12 × 27 = 81/324
Likewise, for the 2nd fraction, since 81 × 4 = 324,
42/81 = 42 × 4/81 × 4 = 168/324
Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
81/324 < 168/324 or 3/12 < 42/81

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