Subtract 10/18 from 10/21
10/21 - 10/18 is -5/63.
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,
10/21 = 10 × 6/21 × 6 = 60/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
10/18 = 10 × 7/18 × 7 = 70/126 - Subtract the two like fractions:
60/126 - 70/126 = 60 - 70/126 = -10/126 - After reducing the fraction, the answer is -5/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/21-10/18 10/21-20/18 10/42-10/18 10/21-10/36 30/21-10/18 10/21-30/18 10/63-10/18 10/21-10/54 50/21-10/18 10/21-50/18 10/21-10/90 70/21-10/18 10/21-70/18