# Question

Political polls typically sample randomly from the U.S. population to investigate the percentage of voters who favor some candidate or issue. The number of people polled is usually on the order of 1000. Suppose that one such poll asks voters how they feel about the President’s handling of environmental issues. The results show that 575 out of the 1280 people polled say they either approve or strongly approve of the President’s handling. Find a 95% confidence interval for the proportion of the entire voter population who approve or strongly approve of the President’s handling. If the same sample proportion were found in a sample twice as large—that is 1150 out of 2560— how would this affect the confidence interval? How would the confidence interval change if the confidence level were 90% instead of 95%?

## Answer to relevant Questions

Referring to the previous problem, you often hear the results of such a poll in the news. In fact, the newscasters usually report something such as, “44.9% of the population approve or strongly approve of the President’s ...The file P08_07.xlsx contains a random sample of 200 service times during the busiest hour of the day at a particular fast-food restaurant. Find a 95% confidence interval for each of the following population parameters. Then ...Find a 95% confidence interval for the difference between the following two proportions: the proportion of female customers who order during the evening and the proportion of male customers who order during the evening.Construct a histogram of the PCKnowledge variable. Repeat this separately for those who own a PC and those who do not. Then find a 95% confidence interval for the mean value of PCKnowledge for all of SoftBus’s prospective ...The file P08_77.xlsx contains data on 856 customers who have either tried or not tried a company’s new frozen lasagna dinner. The manager of the company would like to compare the proportion of customers who have tried the ...Post your question

0