Statisticshard · Past Paper
For a data set with 50 items, the mean is 100. If each of the first 25 items is increased by 2, and each of the last 25 items is decreased by 2, the new mean is:
A102
B98
C100
D101
✓ Correct Answer: C — 100
The total increase (25*2) equals the total decrease (25*2), so the sum and the mean remain unchanged.
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