Nine friends decided to take a challengeduring a weekto see who can run the longest distance, every day they run as much as they can during a week (five working days) and each of them recorded how many kilometres they run per day.

At the end of the week, they presented the total kilometresrun during the week. The result is given bellow:

15, 20, 12, 18, 15, 20, 25, 23, 21

1. What is the sample mean?	A 18.78	B 15	C 20	D 13.89
2. What is the median?	A 18	B 20	C 15	D 19
3. What is the sample standard deviation?	A 3.02	B 4.25	C 5.20	D 4.17

Question 4 - 5 (1 + 1 = 2 marks)

The owner of a large company has asked you about the distribution of the ages of the 1000 employees specifically the mean age and the standard deviation of the ages. To answer the owner's questions, you have taken a sample of 100 employees and have constructed the following distribution table

Age	No. of Employees
20 up to 30	17
30 up to 40	20
40 up to 50	25
50 up to 60	20
60 up to 70	18

4. What is the sample mean?	A 42.9	B 45.2	C 45.7	D 42.0
5. What is the sample standard deviation?	A 13.5	B 3902.2	C 13.48	D 3863.2