Subtract 9/20 from 20/72
20/72 - 9/20 is -31/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
20/72 = 20 × 5/72 × 5 = 100/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
9/20 = 9 × 18/20 × 18 = 162/360 - Subtract the two like fractions:
100/360 - 162/360 = 100 - 162/360 = -62/360 - After reducing the fraction, the answer is -31/180
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/72-9/20 20/72-18/20 20/72-9/40 60/72-9/20 20/72-27/20 20/72-9/60 20/72-45/20 20/72-63/20