Published by:
CGP EDU Academic Team
Published on: August 14, 2026
The mean and standard deviation of 20 observations are found to be 10 and 2 . respectively. On rechecking, it was found that an observation by mistake was taken 8 instead of 12 . The correct standard deviation is
A
1.8
B
1.94
C
D
Text Solution
Verified by ExpertsThe correct answer is:
C
If 8 is replaced by 12 , then 
Correct mean 
Standard deviation 
Now, replaced ' 8 ' observations by ' 12 '
Then, 
Variance of removing observations
Correct standard deviation
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