Subtract 18/12 from 75/81
1st number: 75/81, 2nd number: 1 6/12
75/81 - 18/12 is -31/54.
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,
75/81 = 75 × 4/81 × 4 = 300/324 - Likewise, for the 2nd fraction, since 12 × 27 = 324,
18/12 = 18 × 27/12 × 27 = 486/324 - Subtract the two like fractions:
300/324 - 486/324 = 300 - 486/324 = -186/324 - After reducing the fraction, the answer is -31/54
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 75/81-36/12 75/81-18/24 75/81-54/12 75/81-18/36 75/81-90/12 75/81-18/60 75/81-18/84