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MathsMediumMCQ2023 Ā· 11 Apr Shift 1

Q68.Let sets š“ and šµ have 5 elements each. Let the mean of the elements in sets š“ and šµ be 5 and 8 respectively and the variance of the elements in sets š“ and šµ be 12 and 20 respectively. A new set š¶ of 10 elements is formed by subtracting 3 from each element of š“ and adding 2 to each element of šµ. Then the sum of the mean and variance of the elements of š¶ is (1) 40 (2) 32 (3) 38 (4) 36 JEE Main 2023 (11 Apr Shift 1) JEE Main Previous Year Paper

What This Question Tests

This question evaluates the understanding of how mean and variance change when elements of a set are shifted or scaled, requiring calculation of mean and variance for a new combined set.

Concepts Tested

Mean of a setVariance of a setEffect of change of origin and scale on mean and variance

Formulas Used

Mean(x+c) = Mean(x)+c

Variance(x+c) = Variance(x)

Variance(ax) = a²Variance(x)

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