Subtract 20/42 from 20/56
20/56 - 20/42 is -5/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 42 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
20/56 = 20 × 3/56 × 3 = 60/168 - Likewise, for the 2nd fraction, since 42 × 4 = 168,
20/42 = 20 × 4/42 × 4 = 80/168 - Subtract the two like fractions:
60/168 - 80/168 = 60 - 80/168 = -20/168 - After reducing the fraction, the answer is -5/42
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