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 August 31, 2021 by Amity 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
Answer: 3.14 (choice C) ============================================================ 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 ———- 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 Reply
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
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
———-
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