Subtract 20/45 from 18/80
18/80 - 20/45 is -79/360.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 45 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
18/80 = 18 × 9/80 × 9 = 162/720 - Likewise, for the 2nd fraction, since 45 × 16 = 720,
20/45 = 20 × 16/45 × 16 = 320/720 - Subtract the two like fractions:
162/720 - 320/720 = 162 - 320/720 = -158/720 - After reducing the fraction, the answer is -79/360
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/80-20/45 18/80-40/45 18/80-20/90 54/80-20/45 18/80-60/45 90/80-20/45