Compare 21/12 and 42/15
1st number: 1 9/12, 2nd number: 2 12/15
21/12 is smaller than 42/15
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
21/12 = 21 × 5/12 × 5 = 105/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
42/15 = 42 × 4/15 × 4 = 168/60 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 105/60 < 168/60 or 21/12 < 42/15
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