In: Statistics and Probability
An insurance company sells a policy to airline passengers. If a flier misses the purchased flight due to medical reasons, the policy gives $300 to the flier. Otherwise, there is no return. Records show that about 5% passengers miss flight due to illness. You buy the policy for your next flight. Select the correct statement.
(A) The expected value of the amount of money you receive is $15. (B) The variance of the amount of money you receive is $4275. (C) The amount of money you could receive is either $0 or $300. (D) All of the above are correct.
X: The amount of money you receive (from the policy)
The possible value of X
X=0 if you do not miss the flight or you miss for reasons other than illness;
X= $300 if you miss the flight due to illness.
Given , Records show that about 5% passengers miss flight due to illness
Therefore, Probability that you miss flight due to illness = 5/100 = 0.05
Probability that you don't miss the flight or you miss for reasons other than illness = 1-0.05 =0.95
Therefore P(X=300) = 0.05 ; P(X=0) = 0.95
X: The amount of money you receive
Expected value of X
The expected value of the amount of money you receive is $15
Var(X) = E(X2) -E(X)2
Var(X) = E(X2) -E(X)2 = 4500 - 152 = 4500 - 225 = 4275
The variance of the amount of money you receive is $4275
The possible value of X are 0 or 300
The amount of money you could receive is either $0 or $300
The expected value of the amount of money you receive is $15 - correct
The variance of the amount of money you receive is $4275 - Correct
The amount of money you could receive is either $0 or $300 - Correct
Ans : (D) All of the above are correct.