Subtract 4/15 from 18/42
18/42 - 4/15 is 17/105.
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,
18/42 = 18 × 5/42 × 5 = 90/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
4/15 = 4 × 14/15 × 14 = 56/210 - Subtract the two like fractions:
90/210 - 56/210 = 90 - 56/210 = 34/210 - After reducing the fraction, the answer is 17/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/42-4/15 18/42-8/15 18/84-4/15 18/42-4/30 54/42-4/15 18/42-12/15 18/42-4/45 90/42-4/15 18/42-20/15 18/42-4/75 18/42-28/15