Question

In: Statistics and Probability

There is a store selling newspapers. The number of daily sales X is a random variable...

There is a store selling newspapers. The number of daily sales X is a random variable and its expected value is 100 and the variance is 100. If the profit per one newspaper is 20 yen and the fixed cost is 500 yen per day, what is the variance of the profit per day?


(Answer in the form of an integer or an irreducible fraction.)

Solutions

Expert Solution

E(X) = 100

V(X) = 100

Y = 500 + 20X

V(Y) = 202 * V(X) = 400 * 100 = 4000 (ans)

                                                                                                                                                                                                                                                  


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