A telecommunications company wants to estimate the proportion of households that would purchase an additional telephone line if it were made available at a substantially reduced installation cost. Data are collected from a random sample of 500 households. The results indicate that 140 of the households would purchase the additional telephone line at a reduced installation cost. Complete parts? (a) and? (b) below.
a. Construct a 95?% confidence interval estimate for the population proportion of households that would purchase the additional telephone line.
b. How would the manager in charge of promotional programs concerning residential customers use the results in? (a)?