Compare 15/54 and 42/21
1st number: 15/54, 2nd number: 2 0/21
15/54 is smaller than 42/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
15/54 = 15 × 7/54 × 7 = 105/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
42/21 = 42 × 18/21 × 18 = 756/378 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 105/378 < 756/378 or 15/54 < 42/21
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