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Chapter 10: Q. AP3.27 (page 704)

Suppose the true proportion of people who use public transportation to get to work in the Washington, D.C. area is 0.45. In a simple random sample of 250people who work in Washington, about how far do you expect the sample proportion to be from the true proportion?

a. 0.4975

b. 0.2475

c. 0.0315

d. 0.0009

e.0

Short Answer

Expert verified

The correct option is : (c) 0.0315.

Step by step solution

01

- Given Information

We are given the probability of people who use public transportation to get to work in the Washington D.C. area is 0.45and we are given a sample of 250people . We now need to calculate standard deviation .

02

Explanation 

We need to find standard deviation for given sample . So,

pis the given probability of sample and nis the number of people comprising the sample .

Standard deviation =p(1-p)n蟽=p(1-p)n

蟽=0.45(0.55)250

蟽=0.0315

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