Subtract 21/27 from 70/21
1st number: 3 7/21, 2nd number: 21/27
70/21 - 21/27 is 23/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 21 × 9 = 189,
70/21 = 70 × 9/21 × 9 = 630/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
21/27 = 21 × 7/27 × 7 = 147/189 - Subtract the two like fractions:
630/189 - 147/189 = 630 - 147/189 = 483/189 - After reducing the fraction, the answer is 23/9
- In mixed form: 25/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 70/21-42/27 70/42-21/27 70/21-21/54 70/21-63/27 70/63-21/27 70/21-21/81