Subtract 18/21 from 12/56
12/56 - 18/21 is -9/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
12/56 = 12 × 3/56 × 3 = 36/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
18/21 = 18 × 8/21 × 8 = 144/168 - Subtract the two like fractions:
36/168 - 144/168 = 36 - 144/168 = -108/168 - After reducing the fraction, the answer is -9/14
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