Subtract 7/81 from 42/12
1st number: 3 6/12, 2nd number: 7/81
42/12 - 7/81 is 553/162.
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,
42/12 = 42 × 27/12 × 27 = 1134/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
7/81 = 7 × 4/81 × 4 = 28/324 - Subtract the two like fractions:
1134/324 - 28/324 = 1134 - 28/324 = 1106/324 - After reducing the fraction, the answer is 553/162
- In mixed form: 367/162
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/12-7/81 42/12-14/81 42/24-7/81 42/12-21/81 42/36-7/81 42/12-35/81 42/60-7/81 42/12-49/81 42/84-7/81