Find the standard deviation of the data 4, 6, 8, 10, 12, correct to 2 decimal places (use the population formula).
Answer and explanation
Correct answer: C. 2.83
- Step 1: Mean = 8. Step 2. Sum of squared deviations = 40, so variance = 8. Step 3. Standard deviation = root 8 = 2.83. Answer: 2.83. Why not the others: 8.00: That is the variance, which is not square-rooted. 3.16: That divides by n - 1, the sample formula. 5.66: That doubles the correct value.
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