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Question
Past experience indicates that the variance in the time it takes for a "fast lube" operation to actually complete the lube and oil change for customers is 9.00 minutes. The manager wishes to estimate the mean time with 99 percent confidence and a margin of error of 0.50 minutes. Given this, what must the sample size be?
A) n = 239
B) n = 2149
C) n = 139
D) n = 1245
Answer
This answer is hidden. It contains 10 characters.
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