Subtract 7/81 from 84/21
1st number: 4 0/21, 2nd number: 7/81
84/21 - 7/81 is 317/81.
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,
84/21 = 84 × 27/21 × 27 = 2268/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
7/81 = 7 × 7/81 × 7 = 49/567 - Subtract the two like fractions:
2268/567 - 49/567 = 2268 - 49/567 = 2219/567 - After reducing the fraction, the answer is 317/81
- In mixed form: 374/81
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/21-14/81 84/42-7/81 84/21-21/81 84/63-7/81 84/21-35/81 84/21-49/81