Question 31

Mathematics Statistics Easy

The mean of 25 observations was found to be 38. It was later discovered that 23 and 38 were misread as 25 and 36, then the mean is

(A) 32
(B) 36
(C) 38
(D) 42
View Dynamic Solution & Explanation
Correct Solution: Option C

Step-by-step Solution:

Given that the mean of 25 numbers is 38, and two numbers, 25 and 34, are misread as 23 and 36. The corrected mean is: \[ \text{Corrected mean} = \frac{\{(25 \times 38) - (23 + 36)\} + (25 + 34)}{25}. \] Since the sum of \( 25 + 34 \) is the same as \( 23 + 36 \), the total sum of the numbers remains unchanged. Thus, the mean will not change, and the corrected mean remains: \[ \boxed{38}. \]