Subtract 20/36 from 9/42
9/42 - 20/36 is -43/126.
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,
9/42 = 9 × 6/42 × 6 = 54/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
20/36 = 20 × 7/36 × 7 = 140/252 - Subtract the two like fractions:
54/252 - 140/252 = 54 - 140/252 = -86/252 - After reducing the fraction, the answer is -43/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/42-20/36 9/42-40/36 9/84-20/36 9/42-20/72 27/42-20/36 9/42-60/36 45/42-20/36 63/42-20/36