Subtract 42/27 from 20/81
1st number: 20/81, 2nd number: 1 15/27
20/81 - 42/27 is -106/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 27 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 81 × 1 = 81,
20/81 = 20 × 1/81 × 1 = 20/81 - Likewise, for the 2nd fraction, since 27 × 3 = 81,
42/27 = 42 × 3/27 × 3 = 126/81 - Subtract the two like fractions:
20/81 - 126/81 = 20 - 126/81 = -106/81
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