Compare 21/84 and 90/72
1st number: 21/84, 2nd number: 1 18/72
21/84 is smaller than 90/72
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 84 × 6 = 504,
21/84 = 21 × 6/84 × 6 = 126/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
90/72 = 90 × 7/72 × 7 = 630/504 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 126/504 < 630/504 or 21/84 < 90/72
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