Subtract 70/81 from 3/12
3/12 - 70/81 is -199/324.
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,
3/12 = 3 × 27/12 × 27 = 81/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
70/81 = 70 × 4/81 × 4 = 280/324 - Subtract the two like fractions:
81/324 - 280/324 = 81 - 280/324 = -199/324
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/12-70/81 3/24-70/81 9/12-70/81 3/36-70/81 15/12-70/81 3/60-70/81 21/12-70/81 3/84-70/81