Subtract 10/8 from 81/90
1st number: 81/90, 2nd number: 1 2/8
81/90 - 10/8 is -7/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
81/90 = 81 × 4/90 × 4 = 324/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
10/8 = 10 × 45/8 × 45 = 450/360 - Subtract the two like fractions:
324/360 - 450/360 = 324 - 450/360 = -126/360 - After reducing the fraction, the answer is -7/20
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