Subtract 12/9 from 28/72
1st number: 28/72, 2nd number: 1 3/9
28/72 - 12/9 is -17/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
28/72 = 28 × 1/72 × 1 = 28/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
12/9 = 12 × 8/9 × 8 = 96/72 - Subtract the two like fractions:
28/72 - 96/72 = 28 - 96/72 = -68/72 - After reducing the fraction, the answer is -17/18
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/72-12/9 28/72-24/9 28/72-12/18 84/72-12/9 28/72-36/9 28/72-12/27 28/72-60/9 28/72-12/45 28/72-84/9 28/72-12/63