Subtract 90/7 from 28/12
1st number: 2 4/12, 2nd number: 12 6/7
28/12 - 90/7 is -221/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
28/12 = 28 × 7/12 × 7 = 196/84 - Likewise, for the 2nd fraction, since 7 × 12 = 84,
90/7 = 90 × 12/7 × 12 = 1080/84 - Subtract the two like fractions:
196/84 - 1080/84 = 196 - 1080/84 = -884/84 - After reducing the fraction, the answer is -221/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/12-90/7 28/24-90/7 28/12-90/14 84/12-90/7 28/36-90/7 28/12-90/21 28/60-90/7 28/12-90/35 28/84-90/7 28/12-90/49