Subtract 20/27 from 81/42
1st number: 1 39/42, 2nd number: 20/27
81/42 - 20/27 is 449/378.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 27 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
81/42 = 81 × 9/42 × 9 = 729/378 - Likewise, for the 2nd fraction, since 27 × 14 = 378,
20/27 = 20 × 14/27 × 14 = 280/378 - Subtract the two like fractions:
729/378 - 280/378 = 729 - 280/378 = 449/378 - In mixed form: 171/378
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