Subtract 45/27 from 21/84
1st number: 21/84, 2nd number: 1 18/27
21/84 - 45/27 is -17/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 27 is 756
Next, find the equivalent fraction of both fractional numbers with denominator 756 - For the 1st fraction, since 84 × 9 = 756,
21/84 = 21 × 9/84 × 9 = 189/756 - Likewise, for the 2nd fraction, since 27 × 28 = 756,
45/27 = 45 × 28/27 × 28 = 1260/756 - Subtract the two like fractions:
189/756 - 1260/756 = 189 - 1260/756 = -1071/756 - After reducing the fraction, the answer is -17/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/84-45/27 21/84-90/27 21/84-45/54 63/84-45/27 21/84-45/81