Question: Prior to an election, campaign committees or news organizations sometimes pay for an opinion poll of prospective voters. Suppose that a newspaper reports that, if the election were held now, 52% of voters would vote for candidate X, with a margin of error of plus or minus 3%.

a. If no confidence level is reported for the result, what is the assumed level?

b. What is the minimum number of randomly-selected prospective votes who needed to be polled in order to achieve the level of confidence you assumed in part (a)?

c. Suppose that the poll was conducted as you specified in part (b). Explain what difference it would make to your confidence in the statement “52% + 3% of voters would choose candidate X,” if the poll were used to predict a local election, versus a national one.

d. Discuss whether the poll result implies that candidate X will win a majority of the votes.