Just looking for some math checking and if I am worng why

Consider a sample with data values of 27, 25, 23, 15, 30, 33, 28, and 25. Compute the range, interquartile range, variance, and standard deviation (to a maximum of 2 decimals, if decimals are necessary).

Range

34

Interquartile range

3

Variance

25.19

Standard deviation

5.02

==========

The budgeting process for a midwestern college resulted in expense forecasts for the coming year (in $ millions) of $9, $10, $11, $12, and $13. Because the actual expenses are unknown, the following respective probabilities are assigned: 0.26, 0.17, 0.23, 0.15, and 0.19.

1. Show the probability distribution for the expense forecast.

x f(x)

9 .26

10 .17

11 .23

12 .15

13 .19

What is the expected value of the expense forecast for the coming year (to 2 decimals)?

10.84

What is the variance of the expense forecast for the coming year (to 2 decimals)?

2.09

If income projections for the year are estimated at $12 million, how much profit does the college expect to make (report your answer in millions of dollars, to 2 decimals)?

1.16

===========