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JEE MATHEMATICS MCQ: STATISTICS

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Application +4 | -1

If

\sum\limits_{{i=1}}^5 x_i^2=40 \& \sum\limits_{{i=6}}^{10} x_j^2=20

and mean of

x_1, x_2, \ldots \ldots x_5

, is 1 and mean of

x_6, x_7, \ldots \ldots . . . x_{10}

is 2 then variance of

x_1, x_2, \ldots \ldots . . x_{10}

is

View answer and explanation

Correct option: B

\frac{15}{4}

Option B (

\frac{15}{4}

) is correct because it is the variance calculated using the given sums of squares and means.

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\bar X,

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