Subtract 90/9 from 81/30
1st number: 2 21/30, 2nd number: 10 0/9
81/30 - 90/9 is -73/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 9 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
81/30 = 81 × 3/30 × 3 = 243/90 - Likewise, for the 2nd fraction, since 9 × 10 = 90,
90/9 = 90 × 10/9 × 10 = 900/90 - Subtract the two like fractions:
243/90 - 900/90 = 243 - 900/90 = -657/90 - After reducing the fraction, the answer is -73/10
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