# Question: 22 in a sample of 300 adults 52 smoke 22a...

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22. In a sample of 300 adults, 52 smoke. (22.a) Calculate the proportion of smokers in the sample. (Show your calculations.) (22.b) When we use Excel function =CONFIDENCE.T(α,σ,n), we need the value σ. Calculate that σ in this problem. (Show your calculations.) (22.c) Figure out the value E by using Excel function =CONFIDENCE.T(α,σ,n), with allowed error rate 0.05. (22.d) What is the 95% confidence interval of the proportion of smokers in population?