Compare 45/12 and 81/21
1st number: 3 9/12, 2nd number: 3 18/21
45/12 is smaller than 81/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
45/12 = 45 × 7/12 × 7 = 315/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
81/21 = 81 × 4/21 × 4 = 324/84 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 315/84 < 324/84 or 45/12 < 81/21
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