Subtract 1/12 from 42/81
42/81 - 1/12 is 47/108.
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,
42/81 = 42 × 4/81 × 4 = 168/324 - Likewise, for the 2nd fraction, since 12 × 27 = 324,
1/12 = 1 × 27/12 × 27 = 27/324 - Subtract the two like fractions:
168/324 - 27/324 = 168 - 27/324 = 141/324 - After reducing the fraction, the answer is 47/108
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