Subtract 81/90 from 7/8
7/8 - 81/90 is -1/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 8 × 45 = 360,
7/8 = 7 × 45/8 × 45 = 315/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
81/90 = 81 × 4/90 × 4 = 324/360 - Subtract the two like fractions:
315/360 - 324/360 = 315 - 324/360 = -9/360 - After reducing the fraction, the answer is -1/40
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