Subtract 90/12 from 21/56
1st number: 21/56, 2nd number: 7 6/12
21/56 - 90/12 is -57/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 12 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
21/56 = 21 × 3/56 × 3 = 63/168 - Likewise, for the 2nd fraction, since 12 × 14 = 168,
90/12 = 90 × 14/12 × 14 = 1260/168 - Subtract the two like fractions:
63/168 - 1260/168 = 63 - 1260/168 = -1197/168 - After reducing the fraction, the answer is -57/8
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