Compare 45/18 and 81/21
1st number: 2 9/18, 2nd number: 3 18/21
45/18 is smaller than 81/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
45/18 = 45 × 7/18 × 7 = 315/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
81/21 = 81 × 6/21 × 6 = 486/126 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 315/126 < 486/126 or 45/18 < 81/21
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