Subtract 6/12 from 21/81
21/81 - 6/12 is -13/54.
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,
6/12 = 6 × 27/12 × 27 = 162/324 - Subtract the two like fractions:
84/324 - 162/324 = 84 - 162/324 = -78/324 - After reducing the fraction, the answer is -13/54
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