Eric wants to estimate the percentage of elementary school children who have a social media account....

Eric wants to estimate the percentage of elementary school children who have a social media account. He surveys 450 elementary school children and finds that 280 have a social media account. Identify the values needed to calculate a confidence interval at the 99% confidence level. Then find the confidence interval.

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Answer:

Given that:

Eric wants to estimate the percentage of elementary school children who have a social media account. He surveys 450 elementary school children and finds that 280 have a social media account.

Total number of children surveyed = 450

Number of students who have a social media account x = 280

So,the sample proportion of children who have a social media account is compared as shown below

The 99% confidence interval for proportion children who have a social media account is calculated by the following formula

When will be the two tailed critical value of the z-test statistic at 99% level of confidence which is obtained from standard normal table as 2.58.Substitute all the values in the above formula to compute the confidence interval as shown below

Thus,the 99% confidence interval for the true proportion of children who have a social media account is (0.5631,0.6813)

orchestra answered 1 year ago

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