Compare 21/42 and 90/63
1st number: 21/42, 2nd number: 1 27/63
21/42 is smaller than 90/63
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 63 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
21/42 = 21 × 3/42 × 3 = 63/126 - Likewise, for the 2nd fraction, since 63 × 2 = 126,
90/63 = 90 × 2/63 × 2 = 180/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 63/126 < 180/126 or 21/42 < 90/63
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