Subtract 28/42 from 40/21
1st number: 1 19/21, 2nd number: 28/42
40/21 - 28/42 is 26/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
40/21 = 40 × 2/21 × 2 = 80/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
28/42 = 28 × 1/42 × 1 = 28/42 - Subtract the two like fractions:
80/42 - 28/42 = 80 - 28/42 = 52/42 - After reducing the fraction, the answer is 26/21
- In mixed form: 15/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/21-28/42 40/21-56/42 40/42-28/42 40/21-28/84 40/21-84/42 40/63-28/42