Question

The mean of this data set is 6. What is the standard deviation of the data set?
2, 4, 6, 9, 9

Answer 1

a. radical 9.5
b. radical 7.6
c. radical 3
d. radical 38

Answer 2

take each entry and subtract the mean from it, and square your results

add those results together and divide by how many there are.

this number is then the variance and sd = sqrt(variance)

Answer 3

(2-6)^2
(4-6)^2
(6-6)^2
(9-6)^2
+ (9-6)^2
---------
some number

divide that by 5 and you should get the value in your radical