Question

 

In a study of speed dating, male subjects were asked to rate the attractiveness of their female dates, and the sample of the results is listed below (1=not attractive; 10=extremely attractive). Construct a confidence interval using a 90% confidence level.

5, 9, 1, 8, 4, 5, 8, 8, 7, 8, 5, 9

What is the confidence interval for the population mean?

Answer 1

Solution:

We are given that: in a study of speed dating, male subjects were asked to rate the attractiveness of their female dates, and the sample of the results is listed below (1=not attractive; 10=extremely attractive).

5, 9, 1, 8, 4, 5, 8, 8, 7, 8, 5, 9

We have to construct a confidence interval using a 90% confidence level for the population mean.

We use following steps in TI 84 plus calculator:

Step 1) Press STAT and select EDIT

Step 2) Under EDIT select L1 column and delete all existing numbers and enter new numbers given in question.

Step 3) Again press STAT and select TESTS under STAT

Step 4) Under TESTS , select T Interval

Step 5) Under T Interval select Data

Under Data

List: L1

Freq: 1

C-Level : 0.90

Click on Calculate and Press ENTER key

Thus we get following output:

Thus 90% confidence interval for population mean is between : ( 5.1572 , 7.6761 )