Compare 42/81 and 21/18
1st number: 42/81, 2nd number: 1 3/18
42/81 is smaller than 21/18
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 18 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 81 × 2 = 162,
42/81 = 42 × 2/81 × 2 = 84/162 - Likewise, for the 2nd fraction, since 18 × 9 = 162,
21/18 = 21 × 9/18 × 9 = 189/162 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 84/162 < 189/162 or 42/81 < 21/18
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