Q 101

The amount of money that Jon can save after working for a summer is a random variable S with a mean of $1700 and a standard deviation of $100.After saving this money Jon plans to go on a trip to India.He will change his money into Rupees at an exchange rate of 43 Rupees to one Dollar.This money he will bring to India.When he arrives in India he will buy a used motorbike.The price in India of a motorbike of the type he wants is a random variable B with a mean of 18,500 Rupees and a standard deviation of 500 Rupees.The amount of money Jon will have left (in Rupees)after changing his savings into Rupees and buying a motorbike in India is a random variable P.Write an expression for P in terms of S and B.
A)P = 1700S - 18,500B
B)P = 43S - B
C)P = 43S - 18,500
D)P = S/43 - B
E)P = 1700S - B

Q 103

An insurance company estimates that it should make an annual profit of $150 on each homeowner's policy written,with a standard deviation of $6000.If it writes three of these policies,the mean annual profit for the company is found to be The standard deviation of the company's annual profit is found to be What assumptions (if any)underlie the calculation of the mean? of the standard deviation?
A)Mean: that the profit on each policy follows a Normal model Standard deviation: that the policies are independent of one another and that the profit on each policy follows a Normal model
B)Mean: no assumptions required Standard deviation: no assumptions required
C)Mean: no assumptions required Standard deviation: that the policies are independent of one another and that the profit on each policy follows a Normal model
D)Mean: no assumptions required Standard deviation: that the policies are independent of one another
E)Mean: that the policies are independent of one another Standard deviation: that the policies are independent of one another

Q 104

The amount of time it takes to serve each customer in a bank is a random variable with a mean of 3.7 minutes and a standard deviation of 2.1 minutes.When you arrive at the bank there are three customers in front of you.The mean of your wait time is minutes.The standard deviation of your wait time is minutes.What assumptions (if any)underlie the calculation of the mean? of the standard deviation?
A)Mean: that the time for each customer follows a Normal model Standard deviation: that the times for the three customers are independent of one another and that the time for each customer follows a Normal model
B)Mean: that the times for the three customers are independent of one another Standard deviation: that the times for the three customers are independent of one another
C)Mean: no assumptions required Standard deviation: that the times for the three customers are independent of one another
D)Mean: no assumptions required Standard deviation: no assumptions required
E)Mean: no assumptions required Standard deviation: that the times for the three customers are independent of one another and that the time for each customer follows a Normal model