The Amount of Time It Takes to Serve Each Customer

question 37

Multiple Choice

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 3 × 3.7 = 11.1 minutes.The standard deviation of your wait time is
≈ 3.64 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

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Definitions:

NDP

Net Domestic Product (NDP) refers to the total value of all goods and services produced within a country in a specific time period, minus the total value of the goods and services used up in production.

GDP Deflator

An indicator of the price levels for all newly produced domestic final goods and services within an economy, utilized for transforming nominal GDP into real GDP.

Inflation

A universal surge in prices and a dip in the value of monetary assets.

Real GDP

The measure of a country's economic output adjusted for price changes or inflation.