Managers at an automobile manufacturing plant would like to estimate the meancompletion time of an assembly line operation, u. The managers plan to cheese a random sampleof completion times and estimate u via the sample. Assuming that the standard deviationof the population of completion times is 10.4 minutes, what is the minimum sample size needed for the managers to be 95% confident that their estimates is within 2.0 minutes of u?
Carry your intermediate computations to at least three decimal places. Write your answer as a whole number (and make sure that it is the minimum whole number that satisfies the requirements.
The solution examines sample sizes to determine a 95% confidence interval within 2.0 minutes.