Published by:
CGP EDU Academic Team
Published on: August 14, 2026
The mean and variance of a set of 15 numbers are 12 and 14 respectively. The mean and variance of another set of 15 numbers are 14 and 
2 respectively. If the variance of all the 30 numbers in the two sets is 13, then 
2 is equal to
Text Solution
Verified by ExpertsThe correct answer is:
A
Given that,
For set 1 :
Mean = 12 and Variance = 14
For set 2 :
Mean = 14 and Variance = 
2
Now For set 1 we have
Now for set 2 :
Now,
The combined variance will be
Hence, 
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