## 1. Calculate the variance of the set of data to two decimal places. { 1,2,4,4,5,6,6} a. 22 b. 4 c.3.14

Question

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

{ 1,2,4,4,5,6,6}

a. 22
b. 4
c.3.14
d. 1/7
e.2

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2 months 2021-08-31T12:16:32+00:00 1 Answers 0 views 0

1. ### Answer:  3.14 (choice C)

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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