The population proportion is .30. What is the probability that a sample proportion will be within ±.04 of the population proportion for each of the following sample sizes?
a. n = 100
b. n = 200
c. n = 500
d. n = 1000
e. What is the advantage of a larger sample size?
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> The following stocks make up the Dow Jones Industrial Average. Suppose you would like to select a sample of six of these companies to conduct an indepth study of management practices. Use the first two digits in each row of the ninth column of Table 7.
> Assume that we want to identify a simple random sample of 12 of the 372 doctors practicing in a particular city. The doctors’ names are available from a local medical organization. Use the eighth column of five-digit random numbers in T
> Construct a histogram for the data in exercise 12. Exercise 12: Consider the following frequency distribution. Class ……………………………….. Frequency 10–19 …………………………………………. 10 20–29 ………………………………………… 14 30–39 …………………………………………. 17 40–49 …………………………………………. 7 50–5
> The County and City Data Book, published by the Census Bureau, lists information on 3139 counties throughout the United States. Assume that a national study will collect data from 30 randomly selected counties. Use four-digit random numbers from the last
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> Consider the following frequency distribution. Class ……………………………….. Frequency 10–19 …………………………………………. 10 20–29 ………………………………………… 14 30–39 …………………………………………. 17 40–49 …………………………………………. 7 50–59 …………………………………………. 2 Construct a cumulative frequency distribut
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