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Find the standard deviation for each data set. Use the standard deviations to compare the pair of data sets. fastest recorded speeds of various large wild cats (miles per hour):

Find the standard deviation for each data set. Use the standard deviations to compare-example-1
User Mike Aono
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1 Answer

3 votes

Answer: 12.02

Step-by-step explanation:

Calculating the standard deviation of the large wild cats.

The data set is:


70,50,35,50,40,40,35,45,25

The numbers represent speed in miles per hour.

Step 1. The first step is to remember the formula to calculate standard deviation:


\sigma=\sqrt[]{\frac{\sum^{}_{}(x-\operatorname{mean})^2}{n}}

Where

σ --> standard deviation

x --> values from the data set

mean --> mean of the data set

n --> number of values in the data set

∑ --> sum of (x-mean)^2 values for each x value.

Step 2. In our case:


n=9

Let's calculate the mean of the data set by adding all of the values and dividing the result by 9:


\begin{gathered} \operatorname{mean}=(70+50+35+50+40+40+35+45+25)/(9) \\ \downarrow\downarrow \\ \operatorname{mean}=(390)/(9) \end{gathered}

The result is:


\operatorname{mean}=43.333

Step 3. Substitute all of the values into the standard deviation formula:


\begin{gathered} \sigma=\sqrt[]{\frac{\sum^{}_{}(x-\operatorname{mean})^2}{n}} \\ \downarrow\downarrow \\ \sigma=\sqrt[]{((70-43.333)^2+(50-43.333)^2+(35-43.333)^2+(50-43.333)^2+(40-43.333)^(2+)(40-43.333)^2+(35-43.333)^2+(45-43.333)^2+(25-43.333)^2)/(9)} \\ \end{gathered}

The result is:


\sigma=\sqrt[]{(1300)/(9)}

Solving the operations:


\begin{gathered} \sigma=\sqrt[]{144.44} \\ \sigma=12.02 \end{gathered}

Answer: 12.02

User JepZ
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