Question
In: Statistics and Probability
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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Expert Solution
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 agoRelated Solutions
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.
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 500 elementary
school children and finds that 250 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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