Subtract 6/8 from 8/21
8/21 - 6/8 is -31/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
8/21 = 8 × 8/21 × 8 = 64/168 - Likewise, for the 2nd fraction, since 8 × 21 = 168,
6/8 = 6 × 21/8 × 21 = 126/168 - Subtract the two like fractions:
64/168 - 126/168 = 64 - 126/168 = -62/168 - After reducing the fraction, the answer is -31/84
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/21-6/8 8/21-12/8 8/42-6/8 8/21-6/16 24/21-6/8 8/21-18/8 8/63-6/8 8/21-6/24 40/21-6/8 8/21-30/8 8/21-6/40 56/21-6/8 8/21-42/8 8/21-6/56