Statisticshard · Past Paper
If the sum of squares of 10 observations is 250 and their mean is 4, find the variance.
A9
B25
C5
D10
✓ Correct Answer: A — 9
Variance = (Σx^2 / N) - (Mean)^2 = (250 / 10) - (4)^2 = 25 - 16 = 9.
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