Compare 21/42 and 15/7
1st number: 21/42, 2nd number: 2 1/7
21/42 is smaller than 15/7
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 7 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42 - Likewise, for the 2nd fraction, since 7 × 6 = 42,
15/7 = 15 × 6/7 × 6 = 90/42 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 21/42 < 90/42 or 21/42 < 15/7
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