Subtract 72/45 from 20/80
1st number: 20/80, 2nd number: 1 27/45
20/80 - 72/45 is -27/20.
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,
20/80 = 20 × 9/80 × 9 = 180/720 - Likewise, for the 2nd fraction, since 45 × 16 = 720,
72/45 = 72 × 16/45 × 16 = 1152/720 - Subtract the two like fractions:
180/720 - 1152/720 = 180 - 1152/720 = -972/720 - After reducing the fraction, the answer is -27/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/80-72/45 20/80-72/90 60/80-72/45