Subtract 8/18 from 30/21
1st number: 1 9/21, 2nd number: 8/18
30/21 - 8/18 is 62/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
30/21 = 30 × 6/21 × 6 = 180/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
8/18 = 8 × 7/18 × 7 = 56/126 - Subtract the two like fractions:
180/126 - 56/126 = 180 - 56/126 = 124/126 - After reducing the fraction, the answer is 62/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/21-8/18 30/21-16/18 30/42-8/18 30/21-8/36 90/21-8/18 30/21-24/18 30/63-8/18 30/21-8/54 30/21-40/18 30/21-8/90 30/21-56/18