Compare 81/21 and 63/18
1st number: 3 18/21, 2nd number: 3 9/18
81/21 is greater than 63/18
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
81/21 = 81 × 6/21 × 6 = 486/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
63/18 = 63 × 7/18 × 7 = 441/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 486/126 > 441/126 or 81/21 > 63/18
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