Subtract 15/21 from 1/2
1/2 - 15/21 is -3/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
1/2 = 1 × 21/2 × 21 = 21/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
15/21 = 15 × 2/21 × 2 = 30/42 - Subtract the two like fractions:
21/42 - 30/42 = 21 - 30/42 = -9/42 - After reducing the fraction, the answer is -3/14
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 1/2-30/21 1/4-15/21 1/2-15/42 3/2-15/21 1/2-45/21 1/6-15/21 1/2-15/63 5/2-15/21 1/2-75/21 1/10-15/21 7/2-15/21 1/14-15/21