Compare 81/90 and 3/21
81/90 is greater than 3/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
81/90 = 81 × 7/90 × 7 = 567/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
3/21 = 3 × 30/21 × 30 = 90/630 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 567/630 > 90/630 or 81/90 > 3/21
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