Compare 90/21 and 81/40
1st number: 4 6/21, 2nd number: 2 1/40
90/21 is greater than 81/40
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
90/21 = 90 × 40/21 × 40 = 3600/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
81/40 = 81 × 21/40 × 21 = 1701/840 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 3600/840 > 1701/840 or 90/21 > 81/40
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