The average cost of tuition and room and board at a small private liberal arts college is reported to be $8,500 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,745. The population standard deviation is $1,200. Let ? = 0.05. What is the test statistic for this test?


A. ±3.82

B. +0.204

C. -3.82

D. +3.82

Respuesta :

Answer:

D) + 3.82

Z- test statistic value = 3.819≅ 3.82

Step-by-step explanation:

Explanation:-

Given data the sample size 'n' = 350

Population mean  'μ' = $8,500

Sample mean 'x⁻' = $8,500

The population standard deviation is 'σ' = $1,200

The level of significance ∝ =0.05

The tabulated value Z₀.₉₅ = 1.96

Null hypothesis: There is no significant difference between the small private liberal arts college and the financial administrator.

  x⁻= μ

Alternative hypothesis:  x⁻> μ

Test statistic

                        [tex]Z = \frac{x^{-} -mean }{\frac{S.D}{\sqrt{n} } }[/tex]

                       [tex]Z = \frac{8745-8500}{\frac{1200}{\sqrt{350} } }[/tex]

On calculation , we get

                      [tex]Z = \frac{245}{64.14} = 3.819[/tex]

Z- test statistic value = 3.819≅ 3.82

Conclusion:-

The calculated value = 3.82 > 1.96 at 0.05 level of significance.

The null hypothesis is rejected

Alternative hypothesis is accepted

The financial administrator believes that the average cost is higher than the  small private liberal arts college