Subtract 28/21 from 1/72
1st number: 1/72, 2nd number: 1 7/21
1/72 - 28/21 is -95/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
1/72 = 1 × 7/72 × 7 = 7/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
28/21 = 28 × 24/21 × 24 = 672/504 - Subtract the two like fractions:
7/504 - 672/504 = 7 - 672/504 = -665/504 - After reducing the fraction, the answer is -95/72
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/72-28/21 1/72-56/21 1/72-28/42 3/72-28/21 1/72-84/21 1/72-28/63 5/72-28/21 7/72-28/21