Subtract 90/9 from 81/12
1st number: 6 9/12, 2nd number: 10 0/9
81/12 - 90/9 is -13/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 9 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
81/12 = 81 × 3/12 × 3 = 243/36 - Likewise, for the 2nd fraction, since 9 × 4 = 36,
90/9 = 90 × 4/9 × 4 = 360/36 - Subtract the two like fractions:
243/36 - 360/36 = 243 - 360/36 = -117/36 - After reducing the fraction, the answer is -13/4
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