SOLUTION: 7 squirrels were found to have an average weight of 9.4 ounces with a sample standard deviation is 0.9. Find the 95% confidence interval of the true mean weight.
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-> SOLUTION: 7 squirrels were found to have an average weight of 9.4 ounces with a sample standard deviation is 0.9. Find the 95% confidence interval of the true mean weight.
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Question 1069495: 7 squirrels were found to have an average weight of 9.4 ounces with a sample standard deviation is 0.9. Find the 95% confidence interval of the true mean weight. Answer by addingup(3677) (Show Source):
You can put this solution on YOUR website! The general formula for a confidence interval around a population mean (µ) is:
Xbar ± Zα/2[S/√N]
Where Xbar is the mean of your sample (= 9.4)
S is the sample standard deviation (= 0.9)
N is the number of samples ( = 7)
Z(sub)α/2 is the Z-value in the standard normal table. In this case Zα/2 = 1.96. (95% confidence interval, Z-value table is usually at the end of your book)
So your 95% confidence interval is:
:
µ =Xbar ± Zα/2[S/√N]
µ = 9.4 ± 1.96[0.9/√7]
µ = 9.4 ± 0.0.6667
µ is approximately 8.733 or 10.067
