The Bradfield Container Company Makes "Cardboard" Boxes for Commercial Use

The Bradfield Container Company makes "cardboard" boxes for commercial use (i.e. ,pizza boxes).One of the big issues for the company is the set-up time required to change over from one order to the next.At one particular machine,the set-up time is thought to be uniformly distributed between 10 and 21 minutes.To test whether this is true or not,a random sample of 180 set-ups on this machine was selected with set-up time rounded to the nearest two-minute intervals.The following results occurred:
Set-up Time Frequency
10-11 minutes 13
12-13 minutes 23
14-15 minutes 40
16-17 minutes 44
18-19 minutes 40
20-21 minutes 20
a.What are the appropriate null and alternative hypothesis to be tested?
b.Based on the null and alternative hypotheses stated in part a,determine the expected frequencies for each set-up time category.
c.Assuming that we wish to conduct the hypothesis test at the .05 level,what is the critical value that should be used?
d.Compute the test statistic and carry out the hypothesis test.