Subtract 70/81 from 28/36
28/36 - 70/81 is -7/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 36 × 9 = 324,
28/36 = 28 × 9/36 × 9 = 252/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
70/81 = 70 × 4/81 × 4 = 280/324 - Subtract the two like fractions:
252/324 - 280/324 = 252 - 280/324 = -28/324 - After reducing the fraction, the answer is -7/81
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/36-70/81 28/72-70/81 84/36-70/81