Subtract 90/9 from 81/40
1st number: 2 1/40, 2nd number: 10 0/9
81/40 - 90/9 is -319/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 9 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
81/40 = 81 × 9/40 × 9 = 729/360 - Likewise, for the 2nd fraction, since 9 × 40 = 360,
90/9 = 90 × 40/9 × 40 = 3600/360 - Subtract the two like fractions:
729/360 - 3600/360 = 729 - 3600/360 = -2871/360 - After reducing the fraction, the answer is -319/40
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