Subtract 50/56 from 20/42
20/42 - 50/56 is -5/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 56 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 42 × 4 = 168,
20/42 = 20 × 4/42 × 4 = 80/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
50/56 = 50 × 3/56 × 3 = 150/168 - Subtract the two like fractions:
80/168 - 150/168 = 80 - 150/168 = -70/168 - After reducing the fraction, the answer is -5/12
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