Sentences were chosen at random from Michio Kaku's book The Future of the Mind. The number of words in the sentences were counted. This is the result.

7

21

22

4

22

8

7

16

6

12

15

5

4

3

6

21

22

3

16

7

20

22

11

18

Problem:

Use the data above to: a) determine the mean and sample standard deviation, b) calculate a 95% margin of error, c) determine the respective confidence interval.