Statisticshard · Past Paper
If the mean of n numbers is x-bar, and each number is increased by 1, 2, 3, ... n respectively, what is the new mean?
Ax-bar + n
Bx-bar + (n+1)/2
Cx-bar + n/2
Dx-bar + 1
✓ Correct Answer: B — x-bar + (n+1)/2
The sum increases by 1+2+...+n = n(n+1)/2. The mean increases by [n(n+1)/2] / n = (n+1)/2.
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