Subtract 8/90 from 4/80
4/80 - 8/90 is -7/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 90 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
4/80 = 4 × 9/80 × 9 = 36/720 - Likewise, for the 2nd fraction, since 90 × 8 = 720,
8/90 = 8 × 8/90 × 8 = 64/720 - Subtract the two like fractions:
36/720 - 64/720 = 36 - 64/720 = -28/720 - After reducing the fraction, the answer is -7/180
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/80-8/90 4/80-16/90 12/80-8/90 4/80-24/90 20/80-8/90 4/80-40/90 28/80-8/90 4/80-56/90