Stat 215 Quiz 7

Stat 215 Quiz 7 - Your Answer Mean = (4)(1) + (3)(3) = 13...

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Stat 215 Quiz 7 Module: Quiz , Exercise: LinearComb Question Let X1 be N(4, 9) and X2 be N(3, 7). If Y = X1 + 3*X2, determine the mean and variance of Y. Is Y normally distributed? Explain. Answer E(Y) = 1(4) + 3(3) = 13, V(Y) = 1(9) + 9(7) = 72, Yes, linear combinations of normal variables are normal.
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Unformatted text preview: Your Answer Mean = (4)(1) + (3)(3) = 13 Variance = (9)(1) + (3)^2(7) = 72 The Y set will be normally distributed since both subsets were normally distributed and Y is the sum of them. Grader Comments (none) Grade 10.0 (out of 10.0) Total 10.0 (out of 10.0...
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This note was uploaded on 04/03/2008 for the course STAT 215 taught by Professor Dr. during the Spring '08 term at WVU.

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