Compute the mean and variacne of the following probability d
Compute the mean and variacne of the following probability distribution.(Round your answer to 2 decimal place
| X | P(X) | 
| 3 | .1 | 
| 6 | .25 | 
| 9 | .30 | 
| 12 | .35 | 
Solution
Consider the table:
Thus,      
       
 E(x) = Expected value = mean =    8.7 [ANSWER]
 Var(x) = E(x^2) - E(x)^2 =    8.91 [ANSWER]
| x | P(x) | x P(x) | x^2 P(x) | 
| 3 | 0.1 | 0.3 | 0.9 | 
| 6 | 0.25 | 1.5 | 9 | 
| 9 | 0.3 | 2.7 | 24.3 | 
| 12 | 0.35 | 4.2 | 50.4 | 

