JEE MATHEMATICS MCQ: STATISTICS

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The number of observations in a group is 40 . If the average of first 10 is 4.5 and that of the remaining 30 is 3.5 , then the average of the whole group is

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Correct option: A

\frac{15}{4}

Option A (

\frac{15}{4}

) is correct because it is the weighted average of the two groups.

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