Subtract 81/7 from 90/8
1st number: 11 2/8, 2nd number: 11 4/7
90/8 - 81/7 is -9/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 7 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 8 × 7 = 56,
90/8 = 90 × 7/8 × 7 = 630/56 - Likewise, for the 2nd fraction, since 7 × 8 = 56,
81/7 = 81 × 8/7 × 8 = 648/56 - Subtract the two like fractions:
630/56 - 648/56 = 630 - 648/56 = -18/56 - After reducing the fraction, the answer is -9/28
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