Subtract 21/56 from 12/42
12/42 - 21/56 is -5/56.
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,
12/42 = 12 × 4/42 × 4 = 48/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
21/56 = 21 × 3/56 × 3 = 63/168 - Subtract the two like fractions:
48/168 - 63/168 = 48 - 63/168 = -15/168 - After reducing the fraction, the answer is -5/56
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