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Find the mean, variance, and standard deviation for the data set.7, 13, 8, 3, 11, 7, 14, 7, 18, 2The mean is x =(Round to two decimal places as needed.)The variance is 3 =$0(Round to two decimal places as needed.)The standard deviation is on(Round to two decimal places as needed.)

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SOLUTION

Step1; Write out the set of data

7, 13, 8, 3, 11, 7, 14, 7, 18, 2

The mean is given as


\bar{x}=\frac{\text{SUM OF DATA}}{frequency}
\bar{x}=(2+3+7+7+7+8+11+13+14+18)/(10)=(90)/(10)=9

The mean is 9.00

The variance of a set of data is given as


\sigma^2=\frac{\sum (x-\bar{x})^2}{n}

consider the table below


\begin{gathered} (\sigma^2=(2-9)^2+(3-9)^2+(7-9)^2+(7-9)^2+(7-9)^2+(8-9)^2+(11-9)^2+(13-9)+(14-9)^2+(18-9)^2)/(10) \\ \end{gathered}

Hence the variance becomes


\sigma^2=(49+36+4+4+4+1+4+16+25+81)/(10)_{}
\sigma^2=(224)/(10)=22.40

The variance is 22.40

The standard deviation is given as


\begin{gathered} \text{std}=\sqrt[]{variance} \\ \sigma=\sqrt[]{22.40}=4.73 \end{gathered}

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