Question

One cable company claims that it has excellent customer service. In fact, the company advertises that a technician will arrive within 35 minu a service call is placed. One frustrated customer believes this is not accurate, claiming that it takes over 35 minutes for the cable technician The customer asks a simple random sample of 4 other cable customers how long it has taken for the cable technician to arrive when they ha for one. The sample mean for this group is 39.1 minutes with a standard deviation of 2.6 minutes. Assume that the population distribution approximately normal. Test the customer's claim at the 0.10 level of significance. Step 3 of 3: Draw a conclusion and interpret the decision. Answer 4 Points Keyboards We fall to reject the null hypothesis and conclude that there is insufficient evidence at a 0.10 level of significance that it takes over 35 minutes the cable technician to arrive. We reject the null hypothesis and conclude that there is sufficient evidence at a 0.10 level of significance that it takes over 35 minutes for the technician to arrive. We fail to reject the null hypothesis and conclude that there is sufficient evidence at a 0.10 level of significance that it takes over 35 minutes for cable technician to arrive We reject the null hypothesis and conclude that there is insufficient evidence at a 0.10 level of significance that it takes over 35 minutes for the cable technician to arrive.

Answer 1

Hypothesis

$H_0: \mu \leq 35$

$H_1: \mu > 35$

n = 4

$\bar{x}=39.1$

S = 2.6

Test statistics :

$T=\frac{\bar{x}-\mu }{\frac{S}{\sqrt{n}}}$

$T=\frac{39.1-35}{\frac{2.6}{\sqrt{4}}}$

$T=\frac{4.1}{1.3}$

T = 3.1538

df = n-1 = 3

P value :0.02556            

( To get p value use excel command =T.DIST.RT( 3.1538 ,3) )

P value < 0.1 hence we reject null hypothesis

we reject null hypothesis and conclude that there is sufficient evidence at a 0.10 level of significance that takes over 35 minutes for the cable technician to arrive