I believe the answer given is wrong for the following question:
My answer is . The book says that . Who's right?Determine the mean and standard deviation of the random variable whose probability distribution is
x = 2, P(x) = .1
x = 4, P(x) = .2
x = 6, P(x) = .4
x = 8, P(x) = .2
x = 10, P(x) = .1