Subtract 21/72 from 15/75
15/75 - 21/72 is -11/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 72 is 1800
Next, find the equivalent fraction of both fractional numbers with denominator 1800 - For the 1st fraction, since 75 × 24 = 1800,
15/75 = 15 × 24/75 × 24 = 360/1800 - Likewise, for the 2nd fraction, since 72 × 25 = 1800,
21/72 = 21 × 25/72 × 25 = 525/1800 - Subtract the two like fractions:
360/1800 - 525/1800 = 360 - 525/1800 = -165/1800 - After reducing the fraction, the answer is -11/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/75-21/72 15/75-42/72 45/75-21/72 15/75-63/72