Subtract 81/42 from 4/18
1st number: 4/18, 2nd number: 1 39/42
4/18 - 81/42 is -215/126.
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,
81/42 = 81 × 3/42 × 3 = 243/126 - Subtract the two like fractions:
28/126 - 243/126 = 28 - 243/126 = -215/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/18-81/42 4/36-81/42 4/18-81/84 12/18-81/42 4/54-81/42 20/18-81/42 4/90-81/42 28/18-81/42