Subtract 15/20 from 7/40
7/40 - 15/20 is -23/40.
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,
7/40 = 7 × 1/40 × 1 = 7/40 - Likewise, for the 2nd fraction, since 20 × 2 = 40,
15/20 = 15 × 2/20 × 2 = 30/40 - Subtract the two like fractions:
7/40 - 30/40 = 7 - 30/40 = -23/40
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/40-15/20 7/40-30/20 7/80-15/20 7/40-15/40 21/40-15/20 7/40-45/20 7/40-15/60 35/40-15/20 7/40-75/20 49/40-15/20