Published by:
CGP EDU Academic Team
Published on: August 13, 2026
The mean and standard deviation of 40 observations are 30 and 5 respectively. It was noticed that two of these observations 12 and 10 were wrongly recorded. If 
is the standard deviation of the data after omitting the two wrong observations from the data, then 3 8 a 2 is equal to
Text Solution
Verified by ExpertsThe correct answer is:
238
(238)
Wrong mean = 
= 30
Wrong S.D = 
= 5
New sum = 
=1200-10-12 = 1178
New mean = 
New 
= 37000 -(10) 2 -(12) 2 = 36756
New 
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