Asked by Anonymous
Find the mean and standard deviation of the data set. If necessary, round to the nearest hundredth.
4, 8, 5, 12, 3, 9, 5, 2
Mean is 6 and standard deviation is about 13.33?
4, 8, 5, 12, 3, 9, 5, 2
Mean is 6 and standard deviation is about 13.33?
Answers
Answered by
Damon
That standard deviation is much too big. Are you sure it is not the variance and you forgot to take the square root?
Answered by
Anonymous
Oops! I forgot the square root. So would the standard variation be 3.65?
Answered by
Damon
mean is 6 yes
I get sqrt 80 = 8.94 for SD
2^2 + 2^2+1^2+6^2+3^2+3^2+1^2+4^2
4+4+1+36+9+9+1+16 = 80
sqrt 80 = 8.94
I get sqrt 80 = 8.94 for SD
2^2 + 2^2+1^2+6^2+3^2+3^2+1^2+4^2
4+4+1+36+9+9+1+16 = 80
sqrt 80 = 8.94
Answered by
Reiny
Damon, I think you forgot to divide by 7 before taking the square root.
SD = √(80/7) = 3.3806
The amazing Wolfram supports this
http://www.wolframalpha.com/input/?i=standard+deviation+4%2C+8%2C+5%2C+12%2C+3%2C+9%2C+5%2C+2
SD = √(80/7) = 3.3806
The amazing Wolfram supports this
http://www.wolframalpha.com/input/?i=standard+deviation+4%2C+8%2C+5%2C+12%2C+3%2C+9%2C+5%2C+2
Answered by
Damon
whoops, sorry, thanks !