Compare 21/42 and 15/8
1st number: 21/42, 2nd number: 1 7/8
21/42 is smaller than 15/8
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 42 × 4 = 168,
21/42 = 21 × 4/42 × 4 = 84/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
15/8 = 15 × 21/8 × 21 = 315/168 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 84/168 < 315/168 or 21/42 < 15/8
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