Question

A telemarketer is trying two different sales pitches to sell a carpet cleaning service. For Sales Pitch I, he contacted 175 people and 62 of these people bought the cleaning service. For Sales Pitch II, he contacted 154 people and 45 of these people bought the cleaning service. Does this indicate that there is any difference in the population proportions of the people who will buy the cleaning service, depending on which sales pitch he uses? Use a = 0.05.

(a) State the null and alternate hypotheses. Will we use a left-tailed, right-tailed, or two-tailed test? What is the level of significance?
(b) Identify the sampling distribution to be used: standard normal or the Student's t. Compute the z or t value of the sample test statistic and sketch its location.
(c) Find the P value for the sample test statistic.
(d) Should we reject or fail to reject the null hypothesis?

Answer 1