Subtract 81/36 from 21/18
1st number: 1 3/18, 2nd number: 2 9/36
21/18 - 81/36 is -13/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 36 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 18 × 2 = 36,
21/18 = 21 × 2/18 × 2 = 42/36 - Likewise, for the 2nd fraction, since 36 × 1 = 36,
81/36 = 81 × 1/36 × 1 = 81/36 - Subtract the two like fractions:
42/36 - 81/36 = 42 - 81/36 = -39/36 - After reducing the fraction, the answer is -13/12
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