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Chapter 10: Q. 30 (page 670)

Shortly before the2008 presidential election, a survey was taken by the school newspaper at a very large state university. Randomly selected students were asked, “Whom do you plan to vote for in the upcoming presidential election?” Here is a two-way table of the responses by political persuasion for 1850students:

Which of the following statements about these data is true?

(a) The percent of Republicans among the respondents is 41%.

(b) The marginal distribution of the variable choice of candidate is given by Obama: 55.6%; McCain: 37.6%; Other:1.1%; Undecided: 5.7%.

(c) About 11.2%of Democrats reported that they planned to vote for McCain.

(d) About 44.6%of those who are undecided are Independents.

(e) The conditional distribution of political persuasion among those for whom McCain is the candidate of choice is Democrat: 7.5%; Republican: 84.0%; Independent 18.8%:

Short Answer

Expert verified

The correct answer is (d) and (b) (This can be found by taking each row total and dividing by the grand total.)

Step by step solution

01

Given information

We have been given that

Total Republican =712

Total respondents =1850

and we have to find out that which statement is true.

02

Explanation

Now, we will check all the options,

1. As the percentage of republicans is Total republican divided by sample total:

7121850=38%So,(a) is not correct option.

2. Now as the answer is satisfied so b is the correct option.

3.percentage of People planned to vote for McCain is 781037=7.5%so, option c is not correct.

4.As the percentage of people who are independents are 45101=44.6%So, option d is correct.

5.The conditional distribution for democrats is 78695=11.2%so, option e is not correct.

Hence, option b and d are correct.

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Most popular questions from this chapter

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