Subtract 5/7 from 30/21
1st number: 1 9/21, 2nd number: 5/7
30/21 - 5/7 is 5/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
30/21 = 30 × 1/21 × 1 = 30/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
5/7 = 5 × 3/7 × 3 = 15/21 - Subtract the two like fractions:
30/21 - 15/21 = 30 - 15/21 = 15/21 - After reducing the fraction, the answer is 5/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/21-5/7 30/21-10/7 30/42-5/7 30/21-5/14 90/21-5/7 30/21-15/7 30/63-5/7 30/21-5/21 30/21-25/7 30/21-5/35 30/21-35/7 30/21-5/49