Subtract 9/10 from 15/40
15/40 - 9/10 is -21/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 10 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 40 × 1 = 40,
15/40 = 15 × 1/40 × 1 = 15/40 - Likewise, for the 2nd fraction, since 10 × 4 = 40,
9/10 = 9 × 4/10 × 4 = 36/40 - Subtract the two like fractions:
15/40 - 36/40 = 15 - 36/40 = -21/40
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/40-9/10 15/40-18/10 15/80-9/10 15/40-9/20 45/40-9/10 15/40-27/10 15/40-9/30 75/40-9/10 15/40-45/10 15/40-9/50 15/40-63/10 15/40-9/70