Subtract 90/27 from 42/81
1st number: 42/81, 2nd number: 3 9/27
42/81 - 90/27 is -76/27.
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,
42/81 = 42 × 1/81 × 1 = 42/81 - Likewise, for the 2nd fraction, since 27 × 3 = 81,
90/27 = 90 × 3/27 × 3 = 270/81 - Subtract the two like fractions:
42/81 - 270/81 = 42 - 270/81 = -228/81 - After reducing the fraction, the answer is -76/27
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