Subtract 80/81 from 9/21
9/21 - 80/81 is -317/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
9/21 = 9 × 27/21 × 27 = 243/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
80/81 = 80 × 7/81 × 7 = 560/567 - Subtract the two like fractions:
243/567 - 560/567 = 243 - 560/567 = -317/567
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/21-80/81 9/42-80/81 27/21-80/81 9/63-80/81 45/21-80/81 63/21-80/81