A survey of 865 people in one city reveals that 408 have visited a Tim Hortons location in the past week.Construct a 95% confidence interval for the percentage of all people in this city who have visited a Tim Hortons location in the last week.

Question

Quizplus · Accepted Answer

To find the confidence interval, we use the formula:
CI = p̂ ± Z*√(p̂(1-p̂)/n)
where p̂ is the sample proportion (408/865), Z is the Z-score for a 95% confidence level (1.96), and n is the sample size (865).
Plugging in these values, we get:
CI = 0.471 ± 1.96*√[(0.471)(0.529)/865]
CI ≈ (0.438, 0.505)
So the best choice is A, which represents this interval.

A Survey of 865 People in One City Reveals That