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Scoobiegal
06-08-2009, 12:12 AM
A random sample of the commissions earned by local Tupperware dealers last month is given below.

$4377.47 $3183.76 $1970.16 $2270.88 $3860.06
$2508.55 $1569.64 $4205.30 $1663.68 $3960.71

a. Find x-bar and s for this data set.

b. Construct a 99 percent confidence interval for the mean commission earned by local Tupperware dealers. You may assume the commissions are normally distributed.


For A, would I just add them up then divide by 10 for the x-bar? I am not sure how to find the S.

For B. I am not really sure how to go about setting it up.

Thank you so much for your time and for your help.

vicki
06-09-2009, 11:41 PM
You can look up your textbook for the formula. You probably need some software, eg. Excel or Minitab, to calculate the mean, SD, and confidence interval.