Subtract 40/72 from 5/42
5/42 - 40/72 is -55/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
5/42 = 5 × 12/42 × 12 = 60/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
40/72 = 40 × 7/72 × 7 = 280/504 - Subtract the two like fractions:
60/504 - 280/504 = 60 - 280/504 = -220/504 - After reducing the fraction, the answer is -55/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/42-40/72 5/42-80/72 5/84-40/72 15/42-40/72 25/42-40/72 35/42-40/72