statistics
posted by jamie .
In a timeuse study, 20 randomly selected managers were found to spend a mean of 2.40 hours each day on paperwork. The standard deviation of the the 20 scores is 1.30. Also, the sample data appear to have a bellshaped distribution. Construct the 95% confidence interval for the mean time spent on paperwork by all managers.

statistics 
MathGuru
Formula:
CI95 = mean ± 1.96(sd/√n)
Your data:
mean = 2.40
sd = 1.30
n = 20
Plug the values into the formula and calculate the interval.
I hope this will help get you started.
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