Standard Deviation of a Linear Combination
Let X and Y be independent random variables with means μx = 5 and μy = 3, and variances σ²x = 4 and σ²y = 9, respectively. If the random variable W is defined as W = 2X - 3Y, what is the standard deviation of W?
A
√97
B
7
C
√61
D
√43
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