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JEE MATHEMATICS MCQ: STATISTICS

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Application +4 | -1

The mean income of a group of workers is

X

and that of another group is

Y

. If the number of workers in the second group is 10 times the number of workers in the first group, then mean income of combined group is

View answer and explanation

Correct option: B

\frac{X+10 Y}{11}

Option B (

\frac{{X+10Y}}{{11}}

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

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