Let X be a random variable with the following probability di
Let X be a random variable with the following probability distribution: p(3) = 0.25, p(7) = 0.25, p(15) = 0.5. What does E(X) equal?
Solution
Hence E(x) = 10
| x | prob | x*prob | 
| 3 | 0.25 | 0.75 | 
| 7 | 0.25 | 1.75 | 
| 15 | 0.5 | 7.5 | 
| Total | 1 | 10 | 

