Subtract 5/6 from 20/21
20/21 - 5/6 is 5/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 6 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
20/21 = 20 × 2/21 × 2 = 40/42 - Likewise, for the 2nd fraction, since 6 × 7 = 42,
5/6 = 5 × 7/6 × 7 = 35/42 - Subtract the two like fractions:
40/42 - 35/42 = 40 - 35/42 = 5/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21-5/6 20/21-10/6 20/42-5/6 20/21-5/12 60/21-5/6 20/21-15/6 20/63-5/6 20/21-5/18 20/21-25/6 20/21-5/30 20/21-35/6 20/21-5/42