Suppose the following data show the prices of 4 cars with similar characteristics that sold at a recent auction (in thousands of dollars): 6.6, 5, 10.7, 7.3. Calculate the standard deviation of the sample of selling prices. (please express your answer using 2 decimal places)

Answer :

JeanaShupp

Answer: 2.40

Step-by-step explanation:

Given: The prices of 4 cars with similar characteristics that sold at a recent auction (in thousands of dollars): 6.6, 5, 10.7, 7.3.

Let x: 6.6, 5, 10.7, 7.3.

n= 4

Mean : [tex]\overline{x}=\dfrac{\sum x}{n}[/tex]

[tex]\Rightarrow\ \overline{x}=\dfrac{6.6+5+10.7+7.3}{4}\\\\=\dfrac{29.6}{4}\\\\=7.4[/tex]

Now , standard deviation = [tex]\sqrt{\dfrac{\sum(x-\overline{x})^2}{n-1}}[/tex]

[tex]=\sqrt{\dfrac{(6.6-7.4)^2+( 5-7.4)^2+( 10.7-7.4)^2+( 7.3-7.4)^2}{4-1}}\\\\=\sqrt{\dfrac{0.64+5.76+10.89+0.01}{3}}\\\\=\sqrt{\dfrac{17.3}{3}}\approx2.40[/tex]

Hence, the standard deviation of the sample of selling prices = 2.40

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