Statisticshard · Past Paper
If the mean of 7 observations is 18, and one observation 12 is removed, what is the new mean?
A19
B18.5
C20
D17
✓ Correct Answer: A — 19
Old sum = 7 * 18 = 126. New sum = 126 - 12 = 114. New mean = 114 / 6 = 19.
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