Question: In an election campaign, a campaign manager requests that a sample of voters be polled to determine the support for the candidate. From a sample of 175 voters, 91 express plans to support the candidate.

a) What is the point estimate of the proportion of the voters in the population who will support the candidate?

b) Develop and interpret the 95% confidence interval for the proportion of voters in the population who will support the candidate.

c) From the result obtained in (b), is the campaign manager justified in feeling confident that the candidate has the support of at least 50% of the voters? Explain.

d) How many voters should be sampled if we desired to estimate the population proportion with a sampling error of no more than 3%? Continue to use the 95% level of accuracy.