Thread: Word problem dont know where to begin
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Old January 3rd, 2009, 08:25 PM
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Again, post #2 by nzmathman...

Quote:
Originally Posted by nzmathman View Post
b) For any two random variables X and Y, E(X + Y) = E(X) + E(Y) and Var(X + Y) = Var(X) + Var(Y)
In other words, to find the total mean of adult & child tickets combined, add up the individual means. Same with the variances. And remember to square root the variance to get the standard deviation.