The owner of a large car dealership believes that the financial crisis decreased the number of customers visiting her dealership. The dealership has historically had 800 customers per day. The owner takes a sample of 100 days and finds the average number of customers visiting the dealership per day was 750. Assume that the population standard deviation is 350. The value of the test statistic is ________. A) z = -1.429 B) t₉₉ = -1.429 C) z = 1.429 D) t₉₉ = 1.429

Question

Quizplus · Accepted Answer

The test statistic is calculated using the formula for a z-test because the population standard deviation is known. The formula is $z = \frac{\bar{x} - \mu}{(\sigma/\sqrt{n})}$, where $\bar{x}$ is the sample mean, $\mu$ is the population mean, $\sigma$ is the population standard deviation, and $n$ is the sample size. Plugging in the given values: $z = \frac{750 - 800}{(350/\sqrt{100})} = \frac{-50}{35} = -1.429$.

The Owner of a Large Car Dealership Believes That the Financial