Answer:
{13.7756,18.2244}
Explanation:
Given the sample size, the margin of error can be calculated with the formula
where Z is the critical value for the desired confidence level, σ is the population standard deviation, and n is the sample size. Therefore, our margin of error for a 90% confidence level is:
The formula for a confidence interval is
where x-bar is the sample mean. Therefore, the 90% confidence interval for the mean amount of sushi pieces a person can eat is:
Therefore, we are 90% confident that the true mean amount of sushi pieces a person can eat is contained within the interval {13.7756,18.2244}