Compare 21/42 and 90/12
1st number: 21/42, 2nd number: 7 6/12
21/42 is smaller than 90/12
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
90/12 = 90 × 7/12 × 7 = 630/84 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 42/84 < 630/84 or 21/42 < 90/12
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