I found out E(X) by multiplying x with their probabilities and found out (E(x))^2 and E(X^2) but I got the answers in the form of a and b while in the answers, it is given as "2 by symmetry" what does this mean and how do I do this. I would appreciate it if any of you show me the working to it as well
I found out E(X) by multiplying x with their probabilities and found out (E(x))^2 and E(X^2) but I got the answers in the form of a and b while in the answers, it is given as "2 by symmetry" what does this mean and how do I do this. I would appreciate it if any of you show me the working to it as well
This distribution is symmetric. Notice that the probability a appears twice, and b is wedged in between. So expectation is precisely the middle one.