Compare 18/42 and 81/21
1st number: 18/42, 2nd number: 3 18/21
18/42 is smaller than 81/21
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
18/42 = 18 × 1/42 × 1 = 18/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
81/21 = 81 × 2/21 × 2 = 162/42 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 18/42 < 162/42 or 18/42 < 81/21
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