Compare 90/81 and 81/21
1st number: 1 9/81, 2nd number: 3 18/21
90/81 is smaller than 81/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 21 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
90/81 = 90 × 7/81 × 7 = 630/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
81/21 = 81 × 27/21 × 27 = 2187/567 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 630/567 < 2187/567 or 90/81 < 81/21
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