Subtract 12/40 from 7/28
7/28 - 12/40 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 28 × 10 = 280,
7/28 = 7 × 10/28 × 10 = 70/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
12/40 = 12 × 7/40 × 7 = 84/280 - Subtract the two like fractions:
70/280 - 84/280 = 70 - 84/280 = -14/280 - After reducing the fraction, the answer is -1/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/28-12/40 7/28-24/40 7/56-12/40 7/28-12/80 21/28-12/40 7/28-36/40 7/84-12/40 35/28-12/40 7/28-60/40 49/28-12/40 7/28-84/40