Subtract 28/8 from 21/36
1st number: 21/36, 2nd number: 3 4/8
21/36 - 28/8 is -35/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 36 × 2 = 72,
21/36 = 21 × 2/36 × 2 = 42/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
28/8 = 28 × 9/8 × 9 = 252/72 - Subtract the two like fractions:
42/72 - 252/72 = 42 - 252/72 = -210/72 - After reducing the fraction, the answer is -35/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/36-28/8 21/36-56/8 21/72-28/8 21/36-28/16 63/36-28/8 21/36-84/8 21/36-28/24 21/36-28/40 21/36-28/56