Compare 12/21 and 42/54
12/21 is smaller than 42/54
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
12/21 = 12 × 18/21 × 18 = 216/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
42/54 = 42 × 7/54 × 7 = 294/378 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 216/378 < 294/378 or 12/21 < 42/54
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