Subtract 70/36 from 81/42
1st number: 1 39/42, 2nd number: 1 34/36
81/42 - 70/36 is -1/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 42 × 6 = 252,
81/42 = 81 × 6/42 × 6 = 486/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
70/36 = 70 × 7/36 × 7 = 490/252 - Subtract the two like fractions:
486/252 - 490/252 = 486 - 490/252 = -4/252 - After reducing the fraction, the answer is -1/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/84-70/36 81/42-70/72