Subtract 70/21 from 81/4
1st number: 20 1/4, 2nd number: 3 7/21
81/4 - 70/21 is 203/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
81/4 = 81 × 21/4 × 21 = 1701/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
70/21 = 70 × 4/21 × 4 = 280/84 - Subtract the two like fractions:
1701/84 - 280/84 = 1701 - 280/84 = 1421/84 - After reducing the fraction, the answer is 203/12
- In mixed form: 1611/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/8-70/21 81/4-70/42 81/12-70/21 81/4-70/63 81/20-70/21 81/28-70/21