Subtract 1/72 from 30/21
1st number: 1 9/21, 2nd number: 1/72
30/21 - 1/72 is 713/504.
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,
30/21 = 30 × 24/21 × 24 = 720/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
1/72 = 1 × 7/72 × 7 = 7/504 - Subtract the two like fractions:
720/504 - 7/504 = 720 - 7/504 = 713/504 - In mixed form: 1209/504
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/21-1/72 30/21-2/72 30/42-1/72 90/21-1/72 30/21-3/72 30/63-1/72 30/21-5/72 30/21-7/72