# 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?

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1. That standard deviation is much too big. Are you sure it is not the variance and you forgot to take the square root?

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2. Oops! I forgot the square root. So would the standard variation be 3.65?

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3. 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

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4. 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

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5. whoops, sorry, thanks !

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