A radio talk show host with a large audience is interested in the proportion p of adults in his listening area who think the drinking age should be lowered to eighteen. To find this out, he poses the following question to his listeners: “Do you think that the drinking age should be reduced to eighteen in light of the fact that 18-year-olds are eligible for military service?” He asks listeners to go to his website and vote “Yes” if they agree the drinking age should be lowered and “No” if not. Of the 100 people who voted, 70 answered “Yes.” Which of the following conditions are violated?

I. Random

II. 10%

III. Large Counts

a. I only

b. II only

c. III only

d. I and II only

e. I, II, and III

Short Answer

Expert verified

The required correct option is(a)

Step by step solution

01

Given information

n=100x=70

02

The objective is to explain which of the conditions for calculating a confidence interval for the population proportion.

Because they were not chosen at random, the condition of random selection is not satisfied. They simply took an answer from people. As a result, the random sample condition is not met.

The sample size should be less than 10%of the total population. In this case, 100represents less than 10%of the large audience set. As a result, this condition was satisfied.

The final condition is that the number of successes and failures must be10. As a result, the number of successes is 70and number failures

=100-7010that is met.

Hence, this condition is met.

Therefore, Only condition of random is not satisfied.

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Most popular questions from this chapter

Prayer in school Refer to Exercise 5.

a. Explain what would happen to the length of the interval if the confidence level were increased to 99%.

b. How would a 95%confidence interval based on double the sample size compare to the original 95%interval?

c. The news article goes on to say: “The theoretical errors do not take into account

additional errors resulting from the various practical difficulties in taking any survey of public opinion.” List some of the “practical difficulties” that may cause errors which are not included in the ±3 percentage point margin of error.

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