Subtract 6/12 from 42/81
42/81 - 6/12 is 1/54.
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,
42/81 = 42 × 4/81 × 4 = 168/324 - Likewise, for the 2nd fraction, since 12 × 27 = 324,
6/12 = 6 × 27/12 × 27 = 162/324 - Subtract the two like fractions:
168/324 - 162/324 = 168 - 162/324 = 6/324 - After reducing the fraction, the answer is 1/54
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/81-6/12 42/81-6/24 42/81-18/12 42/81-6/36 42/81-30/12 42/81-6/60 42/81-42/12 42/81-6/84