Subtract 15/18 from 28/70
28/70 - 15/18 is -13/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 18 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
28/70 = 28 × 9/70 × 9 = 252/630 - Likewise, for the 2nd fraction, since 18 × 35 = 630,
15/18 = 15 × 35/18 × 35 = 525/630 - Subtract the two like fractions:
252/630 - 525/630 = 252 - 525/630 = -273/630 - After reducing the fraction, the answer is -13/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/70-15/18 28/70-30/18 28/70-15/36 84/70-15/18 28/70-45/18 28/70-15/54 28/70-75/18 28/70-15/90