SOLUTION: The average length of time for students to register in the second semester at a certain university has been 55 minutes. A new registration procedure is being tested. If a random sa

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Question 1195846: The average length of time for students to register in the second semester at a certain university has been 55 minutes. A new registration procedure is being tested. If a random sample of 36 students have an average of 50 minutes with standard deviation of 12 minutes under the system, can you conclude that the new system is better is faster the old one? (Use 5% level of significance)

Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website!
Assume normality, random sampling, and sd of sample is unbiased estimator of sd population.
Ho: mu new=mu old
Ha: mu new NE mu old
alpha=0.05 p(reject Ho|Ho true}
test is a t(0.975, df=35)
critical value is |t|> 2.031
t=(50-55)/12/sqrt(36)
=-5*6/12
=-2.5
reject Ho; the evidence supports that the new system is faster than the old one. p-value=0.017.