Find the standard deviation of 4, 6, 8, 10, 12, using the sample formula, to 2 decimal places.
Answer and explanation
Correct answer: A. 3.16
- Step 1: Mean . Deviations squared: , sum .
- Step 2: Divide by : variance .
- Step 3: .
Answer
3.16.
Why not the others: 2.83: the sum of squares was divided by rather than . 10: this is the variance. 8: this is the mean.
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