Subtract 21/9 from 12/84
1st number: 12/84, 2nd number: 2 3/9
12/84 - 21/9 is -46/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 9 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
12/84 = 12 × 3/84 × 3 = 36/252 - Likewise, for the 2nd fraction, since 9 × 28 = 252,
21/9 = 21 × 28/9 × 28 = 588/252 - Subtract the two like fractions:
36/252 - 588/252 = 36 - 588/252 = -552/252 - After reducing the fraction, the answer is -46/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/84-21/9 12/84-42/9 12/84-21/18 36/84-21/9 12/84-63/9 12/84-21/27 60/84-21/9 12/84-21/45 12/84-21/63