Statisticshard · Past Paper
If the mean of $n$ numbers is $M$, and the sum of first $(n-1)$ numbers is $S$, the $n^{th}$ number is:
A$M - S$
B$nM - S$
C$S - M$
D$nM + S$
✓ Correct Answer: B — $nM - S$
Total sum = nM. The nth number = (Total sum) - (Sum of n-1 numbers) = nM - S.
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