Subtract 20/42 from 28/81
28/81 - 20/42 is -74/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 42 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 81 × 14 = 1134,
28/81 = 28 × 14/81 × 14 = 392/1134 - Likewise, for the 2nd fraction, since 42 × 27 = 1134,
20/42 = 20 × 27/42 × 27 = 540/1134 - Subtract the two like fractions:
392/1134 - 540/1134 = 392 - 540/1134 = -148/1134 - After reducing the fraction, the answer is -74/567
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