Subtract 20/56 from 12/72
12/72 - 20/56 is -4/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 56 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
12/72 = 12 × 7/72 × 7 = 84/504 - Likewise, for the 2nd fraction, since 56 × 9 = 504,
20/56 = 20 × 9/56 × 9 = 180/504 - Subtract the two like fractions:
84/504 - 180/504 = 84 - 180/504 = -96/504 - After reducing the fraction, the answer is -4/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/72-20/56 12/72-40/56 36/72-20/56 12/72-60/56 60/72-20/56 84/72-20/56