Subtract 20/56 from 9/42
9/42 - 20/56 is -1/7.
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,
9/42 = 9 × 4/42 × 4 = 36/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
20/56 = 20 × 3/56 × 3 = 60/168 - Subtract the two like fractions:
36/168 - 60/168 = 36 - 60/168 = -24/168 - After reducing the fraction, the answer is -1/7
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