Subtract 81/8 from 90/7
1st number: 12 6/7, 2nd number: 10 1/8
90/7 - 81/8 is 153/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 8 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 7 × 8 = 56,
90/7 = 90 × 8/7 × 8 = 720/56 - Likewise, for the 2nd fraction, since 8 × 7 = 56,
81/8 = 81 × 7/8 × 7 = 567/56 - Subtract the two like fractions:
720/56 - 567/56 = 720 - 567/56 = 153/56 - In mixed form: 241/56
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