Subtract 4/15 from 21/18
1st number: 1 3/18, 2nd number: 4/15
21/18 - 4/15 is 9/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 15 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Likewise, for the 2nd fraction, since 15 × 6 = 90,
4/15 = 4 × 6/15 × 6 = 24/90 - Subtract the two like fractions:
105/90 - 24/90 = 105 - 24/90 = 81/90 - After reducing the fraction, the answer is 9/10
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/18-4/15 21/18-8/15 21/36-4/15 21/18-4/30 63/18-4/15 21/18-12/15 21/54-4/15 21/18-4/45 21/18-20/15 21/90-4/15 21/18-4/75 21/18-28/15