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Question: For the binomial sample information summarized in each part, indicate whether the sample size is large enough to use the methods of this chapter to construct a confidence interval for p.

a. n = 400,p^= .10

b. n = 50,p^= .10

c. n = 20,p^= .5

d. n = 20,p^= .3

Short Answer

Expert verified

Answer

  1. Large
  2. Not large
  3. Not large
  4. Not large

Step by step solution

01

Determining whether the sample size is large when n is 400 and p⏞ is 0.10

a.Theproductofnandpandtheproductofnand(1-)isshownbelow:

As both the values are above 15, the sample size is quite large.

02

Determining whether the sample size is large when n is 50 and p⏜is 0.10


The product of n and pand the product of n and (1-p)is shown below:

As one of the values is not above 15, the sample size is not large.

03

Determining whether the sample size is large when n is 20 and p^ is 0.5

c.

The product of n and and the product of n and (1-) is shown below:

As both the values are not above 15, the sample size is not large.

04

Determining whether the sample size is large when n is 20 and p⏞ is 0.3

d.

The product of n and pand the product of n and (1-width="11">p) is shown below:

As both the values are not above 15, the sample size is not large.

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Most popular questions from this chapter

If nothing is known about p, .5 can be substituted for p in the sample size formula for a population proportion. But when this is done, the resulting sample size may be larger than needed. Under what circumstances will be using p = .5 in the sample size formula yield a sample size larger than needed to construct a confidence interval for p with a specified bound and a specified confidence level?

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