The following exercise may be answered manually or with the assistance of a computer. The name of the file containing the data is shown.

Dataset: [Xr10-25]

The following data represent a random sample of 9 marks (out of 10) on a statistics quiz. The marks are normally distributed with a standard deviation of 2. Estimate the population mean with 90% confidence.

7

9

7

5

4

8

3

10

9

(to 2 decimals)

(to 2 decimals)