Subtract 4/12 from 15/21
15/21 - 4/12 is 8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
15/21 = 15 × 4/21 × 4 = 60/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
4/12 = 4 × 7/12 × 7 = 28/84 - Subtract the two like fractions:
60/84 - 28/84 = 60 - 28/84 = 32/84 - After reducing the fraction, the answer is 8/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/21-4/12 15/21-8/12 15/42-4/12 15/21-4/24 45/21-4/12 15/63-4/12 15/21-4/36 75/21-4/12 15/21-20/12 15/21-4/60 15/21-28/12 15/21-4/84