Published by:
CGP EDU Academic Team
Published on: August 13, 2026
The mean and standard deviation of 15 observations are found to be 8 and 3 respectively. On rechecking it was found that, in the observations, 20 was misread as 5. Then, the correct variance is equal to_______.
Text Solution
Verified by ExpertsThe correct answer is:
17
(17)
We have
Variance 
Now, as per information given in equation
Now, the new 
= log 5 - 5 2 + 20 2 = 1470
And, new 
= (15x8)-5+ (20) = 135
Variance 
=98-81 = 17
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