### The mean of 25 observations was found to be 78.4. But later on it was found that 96 were misread as 69. The correct means is-

A. 76.54 B. 78.4 C. 79.48 D. 81.32 Answer: Option C

### Solution(By Apex Team)

$\begin{array}{l}\text{Correct sum}\\ \text{= (78.4 × 25 + 96 – 69)}\\ =1987\\ \therefore\text{Correct mean}\\ =\Large\frac{1987}{25}\\ =79.48\end{array}$

A. 20
B. 21
C. 28
D. 32

A. 18
B. 20
C. 24
D. 30

A. 10 years
B. 10.5 years
C. 11 years
D. 12 years