Answer: B) 2.9 approximately
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Explanation:
The weird or fancy looking E symbol is the greek uppercase letter sigma. It is effectively the english version of S to represent summation. So we add up all the [tex](x-\overline{x})^2[/tex] terms to get this. Luckily this has already been done for us in the table where they wrote "sum = 34", so [tex]\sum(x-\overline{x})^2 = 34[/tex]
From here, we substitute this into the formula, along with n = 5 since there are 5 items in the original list
So,
[tex]s = \sqrt{\frac{1}{n-1}\sum(x-\overline{x})^2} \\\\s = \sqrt{\frac{1}{5-1}*34} \\\\s = \sqrt{\frac{1}{4}*34} \\\\s = \sqrt{0.25*34} \\\\s = \sqrt{8.5} \\\\s \approx 2.91547594742266 \\\\s \approx 2.9 \\\\[/tex]
This computes the sample standard deviation. To get the population standard deviation, you'd basically change the "n-1" to simply "n", and the rest of the formula is identical.
