Thread: Word problem dont know where to begin
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Old January 3rd, 2009, 07:05 PM
Bradley55 Bradley55 is offline
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Quote:
Originally Posted by Last_Singularity View Post

Then find the squared error of each x_i from that mean and multiply those by their probabilities: (0.4)(0-1)^2 + (0.3)(1-1)^2 + (0.2)(2-1)^2 + (0.1)(3-1)^2. That is your variance.

Remember to square root that to get standard deviation. You should get 1 for both variance and standard deviation.

So I see now that 1 is the mean and ALSO 1 is the standard deviation, because after is square root the variance (1) i get 1 for the Standard Deviation?

Now onto b, ???.