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CGP EDU Academic Team
Published on: August 14, 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 μ is the average marks of girls and σ 2 is the variance of marks of 50 candidates, then μ + σ 2 is equal to .
Text Solution
Verified by ExpertsThe correct answer is:
25
(25)
(variance of boys) n 1 =no. of boys
n 2 =no. of girls
variance of combined series
σ 2 = 8
⇒ μ + σ 2 = 17 + 8 = 25
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