Question

In a law office, the average number of billed hours per day was 150 last year. In the first 85 days of this year, the average number of billed hours per day is 158 with a standard deviation of 65 hours. When testing the hypothesis (at the 10% level of signficance) that the average number of billed hours per day has increased, what is the null and alternative hypotheses (please write out the null and alternative hypotheses below AND on your scratch work...failure to do BOTH will result in 0 points)

Answer 1

There isn't enough evidence to reject H0

Explanation:

Null hypothesis :

H0: μ = 150

H1 : μ > 150

Decision region :

Reject Null if ;

Pvalue < α

Zstatistic = (x - μ) / (s/sqrt(n))

Zstatistic = (158 - 150) / (65/sqrt(85))

Zstatistic = 0.1135

Using the P value calculator from Zstatistic at 90% ; α = 0.10 confidence interval ; one tailed test = 0.128

Pvalue = 0.128

Since ; 0.128 > 0.10

Pvalue > α

We cannot reject H0: