Subtract 40/3 from 21/42
1st number: 21/42, 2nd number: 13 1/3
21/42 - 40/3 is -77/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 3 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42 - Likewise, for the 2nd fraction, since 3 × 14 = 42,
40/3 = 40 × 14/3 × 14 = 560/42 - Subtract the two like fractions:
21/42 - 560/42 = 21 - 560/42 = -539/42 - After reducing the fraction, the answer is -77/6
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 21/42-80/3 21/84-40/3 21/42-40/6 63/42-40/3 21/42-40/9 21/42-40/15 21/42-40/21