Subtract 40/84 from 2/21
2/21 - 40/84 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
2/21 = 2 × 4/21 × 4 = 8/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
40/84 = 40 × 1/84 × 1 = 40/84 - Subtract the two like fractions:
8/84 - 40/84 = 8 - 40/84 = -32/84 - After reducing the fraction, the answer is -8/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 4/21-40/84 2/21-80/84 2/42-40/84 6/21-40/84 2/63-40/84 10/21-40/84 14/21-40/84