Subtract 72/54 from 81/90
1st number: 81/90, 2nd number: 1 18/54
81/90 - 72/54 is -13/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 90 × 3 = 270,
81/90 = 81 × 3/90 × 3 = 243/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
72/54 = 72 × 5/54 × 5 = 360/270 - Subtract the two like fractions:
243/270 - 360/270 = 243 - 360/270 = -117/270 - After reducing the fraction, the answer is -13/30
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