Subtract 45/72 from 9/21
9/21 - 45/72 is -11/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
9/21 = 9 × 24/21 × 24 = 216/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
45/72 = 45 × 7/72 × 7 = 315/504 - Subtract the two like fractions:
216/504 - 315/504 = 216 - 315/504 = -99/504 - After reducing the fraction, the answer is -11/56
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/21-45/72 9/21-90/72 9/42-45/72 27/21-45/72 9/63-45/72 45/21-45/72 63/21-45/72