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