Subtract 28/72 from 18/21
18/21 - 28/72 is 59/126.
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,
18/21 = 18 × 24/21 × 24 = 432/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
28/72 = 28 × 7/72 × 7 = 196/504 - Subtract the two like fractions:
432/504 - 196/504 = 432 - 196/504 = 236/504 - After reducing the fraction, the answer is 59/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/21-28/72 18/21-56/72 18/42-28/72 54/21-28/72 18/21-84/72 18/63-28/72 90/21-28/72