Compare 42/81 and 21/15
1st number: 42/81, 2nd number: 1 6/15
42/81 is smaller than 21/15
Steps for comparing fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 15 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
42/81 = 42 × 5/81 × 5 = 210/405 - Likewise, for the 2nd fraction, since 15 × 27 = 405,
21/15 = 21 × 27/15 × 27 = 567/405 - Since the denominators are now the same, the fraction with the bigger numerator is the greater fraction
- 210/405 < 567/405 or 42/81 < 21/15
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