Question
Problem: The data set represents the amount of time (in minutes) spent checking email for a...
Problem: The data set represents the amount of time (in minutes)
spent checking
email for a random sample of employees at a company.
7.5 2.0 12.1 8.8 9.4 7.3 1.9 2.8 7.0 7.3
1) Find the sample mean and the sample standard deviation.
2) Construct a 90% confidence interval for the population mean.
Interpret the results.
Assume the times are normally distributed.
3) Repeat part (2), assuming σ = 3.5 minutes. Compare the
results.
Homework Answers
Answer #1
(1) I input the data set in R programming software and use the
mean(.) and sd(.) functions to calculate the sample mean and the
sample standard deviation. Sample mean = 
= 6.610, Sample standard deviation = 
= 3.376.
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