Question: A survey of 21,250 households concerning telephone service gave the results shown in the table.
a. Give a point estimate for the proportion of all households in which there is a cell phone but no landline.
b. Assuming the sample is sufficiently large, construct a 99.9% confidence interval for the proportion of all households in which there is a cell phone but no landline.
c. Give a point estimate for the proportion of all households in which there is no telephone service of either kind.
d. Assuming the sample is sufficiently large, construct a 99.9% confidence interval for the proportion of all all households in which there is no telephone service of either kind.