JEE MATHEMATICS MCQ: STATISTICS

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Understanding +4 | -1

Let

x_1, x_2, \ldots, x_n

\mathrm{n}

observations, and let

\bar{x}

be their arithmetic mean and

\sigma^2

be the variance.

Statement-1: Variance of

2 x_1, 2 x_2, \ldots, 2 x_n

4 \sigma^2

.

Statement-2: Arithmetic mean

2 x_1, 2 x_2, \ldots, 2 x_n

4 \bar{x}

View answer and explanation

Correct option: D

Statement-1 is true, statement-2 is false.

Option D is correct. Statement-1 is true because variance is multiplied by the square of the constant, and Statement-2 is false because the arithmetic mean is multiplied by 2, not 4.

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