Subtract 40/21 from 3/42
1st number: 3/42, 2nd number: 1 19/21
3/42 - 40/21 is -11/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
3/42 = 3 × 1/42 × 1 = 3/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
40/21 = 40 × 2/21 × 2 = 80/42 - Subtract the two like fractions:
3/42 - 80/42 = 3 - 80/42 = -77/42 - After reducing the fraction, the answer is -11/6
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/42-40/21 3/42-80/21 3/84-40/21 3/42-40/42 9/42-40/21 3/42-40/63 15/42-40/21 21/42-40/21