Subtract 56/45 from 81/90
1st number: 81/90, 2nd number: 1 11/45
81/90 - 56/45 is -31/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
81/90 = 81 × 1/90 × 1 = 81/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
56/45 = 56 × 2/45 × 2 = 112/90 - Subtract the two like fractions:
81/90 - 112/90 = 81 - 112/90 = -31/90
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Related: 81/90-56/90