Subtract 18/12 from 21/81
1st number: 21/81, 2nd number: 1 6/12
21/81 - 18/12 is -67/54.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 12 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 81 × 4 = 324,
21/81 = 21 × 4/81 × 4 = 84/324 - Likewise, for the 2nd fraction, since 12 × 27 = 324,
18/12 = 18 × 27/12 × 27 = 486/324 - Subtract the two like fractions:
84/324 - 486/324 = 84 - 486/324 = -402/324 - After reducing the fraction, the answer is -67/54
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