The sample survey showed that 72% of Internet users said the Internet has generally strengthened their relationship with family and friends. Develop a 95% confidence interval for the proportion of respondents who say the Internet has strengthened their relationship with family and friends.

The 95% confidence interval for the proportion of respondents who say the Internet has strengthened their relationship with family and friends is:

In which n is the sample size of the survey.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of , and a confidence level of , we have the following confidence interval of proportions.

In which

z is the z-score that has a p-value of .

The sample survey showed that 72% of Internet users said the Internet has generally strengthened their relationship with family and friends.

This means that

95% confidence level

So , z is the value of Z that has a p-value of , so .

Confidence interval:

The 95% confidence interval for the proportion of respondents who say the Internet has strengthened their relationship with family and friends is:

In which n is the sample size of the survey.