What is the variance of the numbers: 2, 4, 6, 8, 10?
Answer and explanation
Correct answer: A. 8
- Step 1: Calculate the mean: (2 + 4 + 6 + 8 + 10) / 5 = 30 / 5 = 6.
- Step 2: Compute squared deviations from the mean: (2-6)^2 = 16, (4-6)^2 = 4, (6-6)^2 = 0, (8-6)^2 = 4, (10-6)^2 = 16.
- Step 3: Sum squared deviations: 16 + 4 + 0 + 4 + 16 = 40.
- Step 4: Divide by N = 5: Variance = 40 / 5 = 8.
Answer
8.
Why not the others: Option sqrt(8) represents the standard deviation rather than the variance. Option 10 is the range or maximum value. Option 6 is the mean.
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