Subtract 40/12 from 90/28
1st number: 3 6/28, 2nd number: 3 4/12
90/28 - 40/12 is -5/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
90/28 = 90 × 3/28 × 3 = 270/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
40/12 = 40 × 7/12 × 7 = 280/84 - Subtract the two like fractions:
270/84 - 280/84 = 270 - 280/84 = -10/84 - After reducing the fraction, the answer is -5/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/28-80/12 90/56-40/12 90/28-40/24 90/84-40/12 90/28-40/36 90/28-40/60 90/28-40/84