The international air transport association surveys business travelers to develop quality ratings for transatlantic gateway airports. the maximum possible rating is 10. suppose a simple random sample of 50 business travelers is selected and each traveler is asked to provide a rating for the miami international airport. the ratings obtained from the sample of 50 business travelers follow.
excel or minitab users: the data set is available in the file named "miami." all data sets can be found in your ebook or on your student cd.
6 4 6 8 7 7 6 3 3 8 10 4 8
7 8 7 5 9 5 8 4 3 8 5 5 4
4 4 8 4 5 6 2 5 9 9 8 4 8
9 9 5 9 7 8 3 10 8 9 6
develop a 95% confidence interval estimate of the population mean rating for miami (to 2 decimals).
95% confidence:
( , )

A confidence interval is a decision criteria used in statistics. There are three decision criteria, the traditional method, the p-value method and the confidence interval. These method are use to decide if the null hypothesis is accepted or rejected.

Using a confidence interval method, we reject the hypothesis if the population parameter has a value outside this interval.

To find the confidence level we have to use this formula: ; where u is the sample mean, o is the standard deviation and n is the sample size.

So, first we have to calculate the mean and standard deviation:

.

Using a 95% of confidence level, the z-value is 1.6.

Now, we can find the confidence interval because we already have all needed values.

Hence, the confidence interval is (6.83;5.85)

hey there!

if she's saving for six months, let's divide the total number we need for the trip by six, dividing it into the amount that needs to be saved for each month.

500 ÷ 6 =

she needs to save at least this amount each month, so we should use this symbol: ≥

let x be the amount she saves each month.

your final answer is x ≥

hope this !