A digital camcorder repair service has set a goal not to exc

A digital camcorder repair service has set a goal not to exceed an average of 5 working days from the time the unit is brought in to the time repairs are completed. A random sample of 12 repair records showed the following repair times (in days): 7, 4, 3, 5, 3, 6, 7, 4, 5, 7, 7, 7. (a) H0: mu 5 days. At a = .05, choose the right option. (b) Calculate the Test statistic. (Round your answer to 3 decimal places.)

Solution

(a) Reject Ho if t >1.796

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(b) sample mean=5.416667

sample standard devation=1.621354

The test statistic is

t=(xbar-mu)/(s/vn)

=(5.416667-5)/(1.621354/sqrt(12))

=0.890