Given Independent Random Variables with Means and Standard Deviations as Shown,find

question 9

Multiple Choice

Given independent random variables with means and standard deviations as shown,find the mean and standard deviation of the variable X - Y.Round to two decimal places if necessary. $$\begin{array} { l | l l } & \text { Mean } & \text { SD } \\\hline \mathrm { X } & 220 & 16 \\\mathrm { Y } & 260 & 12\end{array}$$

• A)? = -40,? = 28
• B)? = 480,? = 20.00
• C)? = -40,? = 20.00
• D)? = -40,? = 10.58
• E)? = -40,? = 4

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