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Statistics question

2023 · 6 Apr · Shift 1 · Q27

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JEE Main
Mathematics
Statistics
2023 · 6 Apr · Shift 1 · Q27

Statistics question

2023 · 6 Apr · Shift 1 · Q27

JEE MainMathematicsStatisticsMCQ+4 / −1

The mean and variance of a set of 15 numbers are 12 and 14 respectively. The mean and variance of another set of 15 numbers are 14 and

\sigma^{2}

respectively. If the variance of all the 30 numbers in the two sets is 13 , then

\sigma^{2}

is equal to :

A
12
B
11
C
10
D
9

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