Subtract 28/40 from 21/2
1st number: 10 1/2, 2nd number: 28/40
21/2 - 28/40 is 49/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 2 × 20 = 40,
21/2 = 21 × 20/2 × 20 = 420/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
28/40 = 28 × 1/40 × 1 = 28/40 - Subtract the two like fractions:
420/40 - 28/40 = 420 - 28/40 = 392/40 - After reducing the fraction, the answer is 49/5
- In mixed form: 94/5
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/2-28/40 21/2-56/40 21/4-28/40 21/2-28/80 63/2-28/40 21/2-84/40 21/6-28/40 21/10-28/40 21/14-28/40