Subtract 21/72 from 5/20
5/20 - 21/72 is -1/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 20 × 18 = 360,
5/20 = 5 × 18/20 × 18 = 90/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Subtract the two like fractions:
90/360 - 105/360 = 90 - 105/360 = -15/360 - After reducing the fraction, the answer is -1/24
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/20-21/72 5/20-42/72 5/40-21/72 15/20-21/72 5/20-63/72 5/60-21/72 25/20-21/72 35/20-21/72