SELF-REVIEW 3-10

EYY

The net incomes of a sample of 20 container shipping companies were organized into the following table:

Net Income (S millions) Number of Companies

2 up to 6

1

6 up to 10

4

10 up to 14

10

14 up to 18

18 up to 22

3

2

(a) What is the table called?

(b) Based on the distribution, what is the estimate of the arithmetic mean net income?

(c) Based on the distribution, what is the estimate of the standard deviation?