Subtract 3/15 from 3/42
3/42 - 3/15 is -9/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
3/42 = 3 × 5/42 × 5 = 15/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
3/15 = 3 × 14/15 × 14 = 42/210 - Subtract the two like fractions:
15/210 - 42/210 = 15 - 42/210 = -27/210 - After reducing the fraction, the answer is -9/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/42-3/15 3/42-6/15 3/84-3/15 3/42-3/30 9/42-3/15 3/42-9/15 3/42-3/45 15/42-3/15 3/42-3/75 21/42-3/15 3/42-21/15