Statisticshard · Past Paper
If for a given data, $\sum (x-5) = 10$ and $n=20$, then the mean is:
A5
B5.5
C4.5
D10
✓ Correct Answer: B — 5.5
$\sum x - \sum 5 = 10 \Rightarrow \sum x - 100 = 10 \Rightarrow \sum x = 110. Mean = 110/20 = 5.5$.
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