## Numerical Measures of Central Tendency and Variability

Read these sections and complete the questions at the end of each section. First, we will define central tendency and introduce mean, median, and mode. We will then elaborate on median and mean and discusses their strengths and weaknesses in measuring central tendency. Finally, we'll address variability, range, interquartile range, variance, and the standard deviation.

### Measures of Variability

#### Questions

**Question 1 out of 4.**

What is the range of 2, 4, 6, and 8?

________

**Question 2 out of 4.**

Would the variance of 10, 12, 17, 20, 25, 27, 42, and 45 be larger if the numbers represented a population or a sample?

- Population
- Sample

**Question 3 out of 4.**

What is the standard deviation of this sample?

________

Y

8

5

11

11

15

9

7

18

**Question 4 out of 4.**

What is the interquartile range of these numbers?

________

Z

12

13

14

15

9

10

16

10

8

10

11

12

13

22

23

24

25