Question

An instructor of a biology class believes the average final exam score for his biology class was more than 75. Suppose a sample of 25 was taken and the sample mean he observed was 78.48 and a standard deviation of 5 points. What is the value of the test statistic?Report your answer to 2 decimal places.

Answer 1

Answer:

The value for the test statistics = 3.48

Step-by-step explanation:

Given that:

population mean $\mu$ = 75

sample size n = 25

sample mean $\overline x$= 78.48

standard deviation = 5

The value for the test statistics can be computed by using the formula:

$z = \dfrac{\overline x- \mu}{\dfrac{\sigma}{\sqrt{n}}}$

$z = \dfrac{78.48- 75}{\dfrac{5}{\sqrt{25}}}$

$z = \dfrac{3.48}{\dfrac{5}{5}}$

z = 3.48

The value for the test statistics = 3.48