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CGP EDU Academic Team
Published on: August 23, 2026
An online exam is attempted by 50 candidates out of which 20 are boys. The average marks obtained by boys is 12 with a variance 2 . The variance of marks obtained by 30 girls is also 2 . The average marks of all 50 candidates is 15. If 
is the average marks of girls and 
is the variance of marks of 50 candidates, then 
is equal to
Text Solution
Verified by ExpertsThe correct answer is:
25
(25)
(variance of boys) 
no. of boys
variance of combined series
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