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A large urgent care Center found that they can see an average of 28 patients per hour assume the standard deviation is 3.3 a random sample of 40 patients were selected find the 95% confidence interval of the mean

User HUA Di
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Answer

The 95% confidence interval of the mean is {26.9766, 28.0234}

Step-by-step explanation

Given data:

Sample mean, x = 28 patients

Standard deviation, s = 3.3

Sample size = 40 patients

z-value for 95% confidence interval = 1.96

The Confidence interval, CI, of the mean the formula is give by:


CI=x\pm z\frac{s}{\sqrt[]{n}}

Substitute the given parameters into the formula to get CI:


\begin{gathered} CI=28\pm1.96*\frac{3.3}{\sqrt[]{40}} \\ CI=28\pm1.96*(3.3)/(6.32) \\ CI=28\pm1.96*0.522151898 \\ CI=28\pm1.0234 \\ CI=\mleft\lbrace28-1.0234,28+1.0234\mright\rbrace \\ CI=\mleft\lbrace26.9766,28.0234\mright\rbrace \end{gathered}

User Ahmed Salman Tahir
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