It has been observed that some persons who suffer

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Question 9   Your answer is CORRECT . Suppose that prior to conducting a coin - flipping experiment , we suspect that the coin is fair . How many times would we have to flip the coin in order to obtain a 90 % confidence interval of width of at most . 18 for the probability of flipping a head ?
a ) 83
b ) 84
c ) 87
d) 50
e) 51
f) None of the above
Question 10   Your answer is CORRECT . It has been observed that some persons who suffer colitis are diagnosed with it again within one year of the first episode . This is due , in part , to damage from the first episode . In order to examine the percentage of the persons who suffer colitis a second time , a random sample of 900 people who suffered colitis was collected . It was observed that 17 of them again suffered colitis within one year . Select a 90 % confidence interval for the true proportion of those who suffer a second episode .
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Question 11   Your answer is CORRECT . When solving for the sample size required to estimate p to within a particular margin of error , under what circumstances do we use p̂ = .5 ?
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Question 12   Your answer is CORRECT . Television viewers often express doubts about the validity of certain commercials . In an attempt to answer their critics , a large advertiser wants to estimate the true proportion of consumers who believe what is shown in commercials . Preliminary studies indicate that about 40 % of those surveyed believe what is shown in commercials . What is the minimum number of consumers that should be sampled by the advertiser to be 85 % confident that their estimate will fall within 2 % of the true population proportion ?
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Question 13   Your answer is CORRECT . An oil company is interested in estimating the true proportion of female truck drivers based in five southern states . A statistician hired by the oil company must determine the sample size needed in order to make the estimate accurate to within 2 % of the true proportion with 97 % confidence . What is the minimum number of truck drivers that the statistician should sample in these southern states in order to achieve the desired accuracy ?
a ) 2944
b ) 2937
c ) 2959
Question 14   Your answer is CORRECT . It has been observed that some persons who suffer colitis , again suffer colitis within one year of the first episode . This is due , in part , to damage from the first episode . The performance of a new drug designed to prevent a second episode is to be tested for its effectiveness in preventing a second episode . In order to do this two groups of people suffering a first episode are selected . There are 112 people in the first group and this group will be administered the new drug . There are 147 people in the second group and this group wil be administered a placebo . After one year , 13 % of the first group has a second episode and 20 % of the second group has a second episode . Select a 99 % confidence interval for the difference in true proportion of the two groups .
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It has been observed that some persons who suffer colitis are diagnosed with it again within one year of the firstepisode. This is due, in part, to damage from the first episode. In order to examine the percentage of the persons whosuffer colitis a second time, a random sample of 900 people who suffered colitis was collected. It was observed that 17of them again suffered colitis within one year. Select a 90% confidence interval for the true proportion of those whosuffer a second episode. a) [0.0154, 0.0364]b) [0.0164, 0.0464]c) [0.0114, 0.0264]d) [0.0134, 0.0764]e) [0.0164, 0.0564]f) None of the above
11/2/2017CourseWare5/6Question 11Your answer is CORRECT.When solving for the sample size required to estimate pto within a particular margin of error, under whatcircumstances do we use p̂ = .5?
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Question 12Your answer is CORRECT.Television viewers often express doubts about the validity of certain commercials. In an attempt to answer their critics,a large advertiser wants to estimate the true proportion of consumers who believe what is shown in commercials.Preliminary studies indicate that about 40% of those surveyed believe what is shown in commercials. What is theminimum number of consumers that should be sampled by the advertiser to be 85% confident that their estimate willfall within 2% of the true population proportion?
Question 13Your answer is CORRECT.

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