Subtract 9/70 from 20/81
20/81 - 9/70 is 671/5670.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 70 is 5670
Next, find the equivalent fraction of both fractional numbers with denominator 5670 - For the 1st fraction, since 81 × 70 = 5670,
20/81 = 20 × 70/81 × 70 = 1400/5670 - Likewise, for the 2nd fraction, since 70 × 81 = 5670,
9/70 = 9 × 81/70 × 81 = 729/5670 - Subtract the two like fractions:
1400/5670 - 729/5670 = 1400 - 729/5670 = 671/5670
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/81-9/70 20/81-18/70 60/81-9/70 20/81-27/70 20/81-45/70 20/81-63/70