Question

Highway transportation officials are trying to determine if the average speed on Archer road is above 45mph, the post speed limit. They took a sample of 50 cars. The sample mean was 44.9 and the standard deviation was 10. Find the test statistic.0.010.0707-0.01-0.0707

Answer 1

Answer:

Option D) -0.0707

Explanation:

We are given the following in the question:  

Population mean, μ = 45 mp

Sample mean, $\bar{x}$ = 44.9

Sample size, n = 50

Sample standard deviation, s = 10

Formula:

$t_{stat} = \displaystyle\frac{\bar{x} - \mu}{\frac{s}{\sqrt{n}} }$

Putting all the values, we have

$t_{stat} = \displaystyle\frac{44.9 - 45}{\frac{10}{\sqrt{50}} } = -0.0707$

Thus, the test statistic is

Option D) -0.0707