Question

What is the standard deviation for the data set: 1, 2, 3, 4, 5, 6, 7, 8, 1000
Please help, I'm so confused. I wrote down the steps and I keep getting 938 but other sites are saying 331.

Answer 1

1st step add the numbers together: 1+2+3+4+5+6+7+8+9+1000 = 1045
2nd step square the total: 1045^2 = 1092025
3rd Step: Divide step 2 by total numbers in set (10) : 1092025 / 10 = 109202.5

4th step, square each number in step 1 and total the squares: 1^2 + 2^2 +3^2 +4^2 +5^2 +6^2 +7^2 +8^2 +9^2 +1000^2 = 1000285

5th step subtract 3rd step from the step: 1000285 - 109202.5 = 891082.5

6th step: divide step 5 by total number is set minus 1 = 891082.5 / 9 = 99009.17

Last step: take square root of step 6 = SQRT(99009.17) = 314.6572

The standard deviation is 314.6572