statistics

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A study of 35 professors showed that the average time they spent creating test questions was 13.5 minutes per question. The standard deviation of the population is 3.8. Which of the following is the 99% confidence interval for the average number of minutes it takes to create a test question?

• statistics -

99% = mean ± 2.575 SEm

SEm = SD/√n

I'll let you do the calculations.

• statistics -

12.0<u<15.0

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