Subtract 90/7 from 81/8
1st number: 10 1/8, 2nd number: 12 6/7
81/8 - 90/7 is -153/56.
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,
81/8 = 81 × 7/8 × 7 = 567/56 - Likewise, for the 2nd fraction, since 7 × 8 = 56,
90/7 = 90 × 8/7 × 8 = 720/56 - Subtract the two like fractions:
567/56 - 720/56 = 567 - 720/56 = -153/56
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