Subtract 15/42 from 4/18
4/18 - 15/42 is -17/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
4/18 = 4 × 7/18 × 7 = 28/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
15/42 = 15 × 3/42 × 3 = 45/126 - Subtract the two like fractions:
28/126 - 45/126 = 28 - 45/126 = -17/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/18-15/42 4/18-30/42 4/36-15/42 4/18-15/84 12/18-15/42 4/18-45/42 4/54-15/42 20/18-15/42 4/18-75/42 4/90-15/42 28/18-15/42