Subtract 90/8 from 72/7
1st number: 10 2/7, 2nd number: 11 2/8
72/7 - 90/8 is -27/28.
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,
72/7 = 72 × 8/7 × 8 = 576/56 - Likewise, for the 2nd fraction, since 8 × 7 = 56,
90/8 = 90 × 7/8 × 7 = 630/56 - Subtract the two like fractions:
576/56 - 630/56 = 576 - 630/56 = -54/56 - After reducing the fraction, the answer is -27/28
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