Subtract 81/90 from 8/12
8/12 - 81/90 is -7/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
8/12 = 8 × 15/12 × 15 = 120/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
81/90 = 81 × 2/90 × 2 = 162/180 - Subtract the two like fractions:
120/180 - 162/180 = 120 - 162/180 = -42/180 - After reducing the fraction, the answer is -7/30
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