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3 years ago

1. Calculate the variance of the set of data to two decimal places.

Mathematics

1 answer:

Komok [63]3 years ago

7 0

<h3>Answer: 3.14 (choice C)</h3>

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Explanation:

First we need the arithmetic mean

Add up the values to get 1+2+4+4+5+6+6 = 28

Divide this over the number of values (n = 7) to get 28/n = 28/7 = 4

The mean is 4.

Next, we subtract the mean from each data value and square the difference

(1-4)^2 = 9
(2-4)^2 = 4
(4-4)^2 = 0
(4-4)^2 = 0
(5-4)^2 = 1
(6-4)^2 = 4
(6-4)^2 = 4

Add up those results: 9+4+0+0+1+4+4 = 22

Lastly, we divide over the number of items (n = 7) to get the population variance: 22/n = 22/7 = 3.14 approximately

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Side note:

If you wanted the sample variance, then you divide over n-1 = 7-1 = 6

22/(n-1) = 22/6 = 3.67 is the approximate sample variance

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