Reference no: EM132401575

a) One division of a large defence contractor manufactures telecommunication equipment for the military. Management wants to determine the percentage of rework for electrical components manufactured by the entire company. The quality of control department wants to estimate the true percentage of rework for electrical components to within 5.0%, with 99% confidence. How many components should they sample at least?

b) Amy is a contestant on a singing reality show. Every week, the public votes for the contestant who they think should win, and the person with the least amount of votes has to leave. Amy is worried that her performance did not go as well and that she may be voted off. Before the public voting officially begins, she tweets to her followers and sets up a poll where she asks them if they would vote for her or not. 9627 people respond, and out of them, 3362 say they would vote for her. Find the 90 percent confidence interval for the true proportion of the votes that Amy will get. Report the minimum proportion of voters that she can be 90% confident will vote for her.

c) McCain Foods produces frozen french fries. suppose one line of french fries has an average length of 7.72cm with a standard deviation of 2.11cm. To make sure that the quality standard is met, they plan to select a random sample of 370 fries a day. Yesterday, the mean was 7.9cm. To calculate the probability that the mean would be 7.9cm or more if they are meeting the quality standards, what is the cutoff z-score?