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

Respuesta :

Answer:

z=3.8196

Step-by-step explanation:

-We notice that this is a normal distribution problem.

-Given the mean is $8500, standard deviation is $1200 , and n=350, the critical z-value using alpha=0.05 is calculated as:

[tex]z=\frac{x-\mu_o}{\sigma/\sqrt{n}}\\\\=\frac{8745-8500}{1200\sqrt{350}}\\\\\\=3.8196[/tex]

Hence, the test statitic is z=3.8196