JEE MATHEMATICS MCQ: STATISTICS

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A sample of 90 values has mean 55 and standard
deviation 3. A second sample of 110 values has mean
60 and standard deviation 2. The combined variance
is equal to (upto two decimal)

View answer and explanation

Correct option: A

12.43

Option A (12.43) is correct because the combined variance is calculated using the formula that accounts for both the individual variances and the differences between the individual means and the overall mean.

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\bar X,

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