Subtract 81/30 from 18/36
1st number: 18/36, 2nd number: 2 21/30
18/36 - 81/30 is -11/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 30 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 36 × 5 = 180,
18/36 = 18 × 5/36 × 5 = 90/180 - Likewise, for the 2nd fraction, since 30 × 6 = 180,
81/30 = 81 × 6/30 × 6 = 486/180 - Subtract the two like fractions:
90/180 - 486/180 = 90 - 486/180 = -396/180 - After reducing the fraction, the answer is -11/5
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