Subtract 18/81 from 7/12
7/12 - 18/81 is 13/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 12 × 27 = 324,
7/12 = 7 × 27/12 × 27 = 189/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
18/81 = 18 × 4/81 × 4 = 72/324 - Subtract the two like fractions:
189/324 - 72/324 = 189 - 72/324 = 117/324 - After reducing the fraction, the answer is 13/36
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