Subtract 15/18 from 28/42
28/42 - 15/18 is -1/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
28/42 = 28 × 3/42 × 3 = 84/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126 - Subtract the two like fractions:
84/126 - 105/126 = 84 - 105/126 = -21/126 - After reducing the fraction, the answer is -1/6
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/42-15/18 28/42-30/18 28/84-15/18 28/42-15/36 84/42-15/18 28/42-45/18 28/42-15/54 28/42-75/18 28/42-15/90