Subtract 70/9 from 81/80
1st number: 1 1/80, 2nd number: 7 7/9
81/80 - 70/9 is -4871/720.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 9 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
81/80 = 81 × 9/80 × 9 = 729/720 - Likewise, for the 2nd fraction, since 9 × 80 = 720,
70/9 = 70 × 80/9 × 80 = 5600/720 - Subtract the two like fractions:
729/720 - 5600/720 = 729 - 5600/720 = -4871/720
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/80-70/18 81/80-70/27 81/80-70/45 81/80-70/63