Question

After the schedule adjustment, the first 36 runs were an average of 8 minutes late. As a result, the Boston public school district claimed that the schedule adjustment was an improvement-students were not as late. Assume a population standard deviation for bus arrival time of 12 minutes. Calculate the value of the test statistic

Answer 1

Answer:

The value of test statistic is -2.

Step-by-step explanation:

The following information is missing in the question.

The population mean is 12 minutes.

We are given the following in the question:

Population mean, μ = 12 minutes

Sample mean, $\bar{x}$ = 8 minutes

Sample size, n = 36

Population standard deviation, σ = 12 minutes

Formula:

$z_{stat} = \displaystyle\frac{\bar{x} - \mu}{\frac{\sigma}{\sqrt{n}} }$

Putting all the values, we have

$z_{stat} = \displaystyle\frac{8 - 12}{\frac{12}{\sqrt{36}} } = -2$

The value of test statistic is -2.