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Chapter 7: Q.6 (page 460)

A researcher initially plans to take anSRS of size n from a population that has a mean of 80 and a standard deviation of 20. If he were to double his sample size (to 2n), the standard deviation of the sampling distribution of the sample mean would be multiplied by

(a) 2.

(b)12 .

(c) 2.

(d) 12.

(e)12n

Short Answer

Expert verified

The correct answer is(b)

Step by step solution

01

Given Information

From the given data, we have,

渭x=渭=80蟽-x=蟽n=20

02

Explanation

Given the sample size is doubled. So nbecomes 2n.

New Standard deviation of the sample distribution is,

localid="1650261481655" 蟽x=蟽2n=12蟽n

Hence the answer is (b)

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