Subtract 81/56 from 21/7
1st number: 3 0/7, 2nd number: 1 25/56
21/7 - 81/56 is 87/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 56 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 7 × 8 = 56,
21/7 = 21 × 8/7 × 8 = 168/56 - Likewise, for the 2nd fraction, since 56 × 1 = 56,
81/56 = 81 × 1/56 × 1 = 81/56 - Subtract the two like fractions:
168/56 - 81/56 = 168 - 81/56 = 87/56 - In mixed form: 131/56
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