Subtract 40/20 from 10/21
1st number: 10/21, 2nd number: 2 0/20
10/21 - 40/20 is -32/21.
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,
10/21 = 10 × 20/21 × 20 = 200/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
40/20 = 40 × 21/20 × 21 = 840/420 - Subtract the two like fractions:
200/420 - 840/420 = 200 - 840/420 = -640/420 - After reducing the fraction, the answer is -32/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/21-40/20 10/21-80/20 10/42-40/20 30/21-40/20 10/63-40/20 10/21-40/60 50/21-40/20 70/21-40/20