Subtract 21/27 from 84/42
1st number: 2 0/42, 2nd number: 21/27
84/42 - 21/27 is 11/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 27 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
84/42 = 84 × 9/42 × 9 = 756/378 - Likewise, for the 2nd fraction, since 27 × 14 = 378,
21/27 = 21 × 14/27 × 14 = 294/378 - Subtract the two like fractions:
756/378 - 294/378 = 756 - 294/378 = 462/378 - After reducing the fraction, the answer is 11/9
- In mixed form: 12/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/42-42/27 84/42-21/54 84/42-63/27 84/42-21/81