Question

The telephone 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. A random sample of 500 households is selected. The results indicate that 135 of the households would purchase that additional telephone line at a reduced installation cost. Set up a 99% confidence interval estimate of the population proportion of households that would purchase the additional telephone line. Provide responses to the following questions related to the confidence interval estimate above:

Provide responses to the following questions related to the confidence interval estimate above:

1. What is the correct z-value for a 99% confidence interval? Remember, if an exact value is not available on the table but you can directly interpolate, provide that value. Otherwise, use the closest value.
2. What is the standard deviation of the sampling proportion (to four decimal places)?
3. Provide (to four decimal places) the confidence interval estimate values:  ≤ p ≤

Answer 1