Subtract 8/20 from 6/21
6/21 - 8/20 is -4/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
6/21 = 6 × 20/21 × 20 = 120/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
8/20 = 8 × 21/20 × 21 = 168/420 - Subtract the two like fractions:
120/420 - 168/420 = 120 - 168/420 = -48/420 - After reducing the fraction, the answer is -4/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 12/21-8/20 6/21-16/20 6/42-8/20 6/21-8/40 18/21-8/20 6/21-24/20 6/63-8/20 6/21-8/60 30/21-8/20 6/21-40/20 42/21-8/20 6/21-56/20