Subtract 12/9 from 20/28
1st number: 20/28, 2nd number: 1 3/9
20/28 - 12/9 is -13/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 9 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
20/28 = 20 × 9/28 × 9 = 180/252 - Likewise, for the 2nd fraction, since 9 × 28 = 252,
12/9 = 12 × 28/9 × 28 = 336/252 - Subtract the two like fractions:
180/252 - 336/252 = 180 - 336/252 = -156/252 - After reducing the fraction, the answer is -13/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/28-12/9 20/28-24/9 20/56-12/9 20/28-12/18 60/28-12/9 20/28-36/9 20/84-12/9 20/28-12/27 20/28-60/9 20/28-12/45 20/28-84/9 20/28-12/63