Subtract 15/20 from 28/40
28/40 - 15/20 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 20 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
28/40 = 28 × 1/40 × 1 = 28/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
15/20 = 15 × 2/20 × 2 = 30/40 - Subtract the two like fractions:
28/40 - 30/40 = 28 - 30/40 = -2/40 - After reducing the fraction, the answer is -1/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/40-15/20 28/40-30/20 28/80-15/20 28/40-15/40 84/40-15/20 28/40-45/20 28/40-15/60 28/40-75/20