Subtract 70/36 from 42/81
1st number: 42/81, 2nd number: 1 34/36
42/81 - 70/36 is -77/54.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 36 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 36 × 9 = 324,
70/36 = 70 × 9/36 × 9 = 630/324 - Subtract the two like fractions:
168/324 - 630/324 = 168 - 630/324 = -462/324 - After reducing the fraction, the answer is -77/54
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/81-70/36 42/81-70/72