Cans of soft drinks cost $0.30 in a certain vending machine. What is the expected value and variance of daily revenue (Y) from the machine, if X, the number of cans sold per day has E(X) = 90, and Var(X) = 40 ( )
A: E(Y ) = 27, Var(Y ) = 4.5
B: E(Y ) = 27 , Var(Y ) = 4.5
C: E(Y ) = 27 , Var(Y ) = 3.6
D: E(Y ) = 90 , Var(Y ) = 3.6
A: E(Y ) = 27, Var(Y ) = 4.5
B: E(Y ) = 27 , Var(Y ) = 4.5
C: E(Y ) = 27 , Var(Y ) = 3.6
D: E(Y ) = 90 , Var(Y ) = 3.6
举一反三
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