#### hustisyawright

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- Thread starter hustisyawright
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Are the data normally distributed?

From the data given to you:

Can you calculate the mean (assuming normal distribution)?

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Since you are given "n= 30" it sounds like you have a binomial distribution with some probability "p". For such a distribution the mean is np= 30p and the standard deviation is \(\displaystyle \sqrt{np(1-p)}\). Knowing the "90% confidence interval" you should be able to calculate p and then the 95% confidence interval.

Thank you. This is very helpful.