Subtract 90/27 from 4/21
1st number: 4/21, 2nd number: 3 9/27
4/21 - 90/27 is -22/7.
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,
4/21 = 4 × 9/21 × 9 = 36/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
90/27 = 90 × 7/27 × 7 = 630/189 - Subtract the two like fractions:
36/189 - 630/189 = 36 - 630/189 = -594/189 - After reducing the fraction, the answer is -22/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/21-90/27 4/42-90/27 4/21-90/54 12/21-90/27 4/63-90/27 4/21-90/81 20/21-90/27 28/21-90/27