Question 471255
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Hi,
 Find the mean and standard deviation of the following probability distribution
x      1    2   3
P(x)  .3   .4  .3

E(x) = 1*.3 +2*.4 +3*.3 = 2
sd = sqrt[(1-2)^2*.3 + (2-2)^2*.4 + (3-2)^2 *.3] = .77