Subtract 3/21 from 15/42
15/42 - 3/21 is 3/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
15/42 = 15 × 1/42 × 1 = 15/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
3/21 = 3 × 2/21 × 2 = 6/42 - Subtract the two like fractions:
15/42 - 6/42 = 15 - 6/42 = 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: 30/42-3/21 15/42-6/21 15/84-3/21 15/42-3/42 45/42-3/21 15/42-9/21 15/42-3/63 75/42-3/21 15/42-15/21