Subtract 81/27 from 20/42
1st number: 20/42, 2nd number: 3 0/27
20/42 - 81/27 is -53/21.
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,
20/42 = 20 × 9/42 × 9 = 180/378 - Likewise, for the 2nd fraction, since 27 × 14 = 378,
81/27 = 81 × 14/27 × 14 = 1134/378 - Subtract the two like fractions:
180/378 - 1134/378 = 180 - 1134/378 = -954/378 - After reducing the fraction, the answer is -53/21
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