Averages: Mean, Median and Mode
Averages give us the "common" value in a set of data. There are 3 ways to measure the average:
| 1. | Mean | ||
is the most commonly used average. It is calculated by adding up the set of values and then dividing that sum, by the number of values used:
| |||
| 2. | Median | ||
| order the set of values by size then work out the middle value | |||
| 3. | Mode | ||
| the value that occurs most often | |||
- Example 1. Find the mean, median and mode of
15 19 10 17 17 16 18 - Example 2. Find the mean, median and mode of
15 22 21 18 15 4 12 5 23
Median
(a) order the numbers
10, 15, 16, 17, 17, 18, 19
(b) find the median which is the middle number:
10, 15, 16, 17, 17, 18, 19 = 17
Mode find the most common value: 17 occurs twice so it is 17
Median
(a) order the numbers
4, 5, 12, 15, 15, 18, 21, 22, 23
(b) find the median which is the middle number:
4, 5, 12, 15, 15, 18, 21, 22, 23 = 15
Mode find the most common value: 15 occurs twice so it is 15
to: 
