Compare 28/21 and 81/42
1st number: 1 7/21, 2nd number: 1 39/42
28/21 is smaller than 81/42
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
28/21 = 28 × 2/21 × 2 = 56/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 56/42 < 81/42 or 28/21 < 81/42
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