1. Calculating the mean
Thursday, 20 September 2018

2. Definition:
The mean is an average of the set of numbers.
To calculate the mean:
 add up all the numbers,
divide this total by how many numbers there are.
In other words mean = 𝑆𝑢𝑚 𝑜𝑓 𝑎𝑙𝑙 𝑡ℎ𝑒 𝑛𝑢𝑚𝑏𝑒𝑟𝑠 ℎ𝑜𝑤 𝑚𝑎𝑛𝑦 𝑛𝑢𝑚𝑏𝑒𝑟𝑠 𝑡ℎ𝑒𝑖𝑟 𝑎𝑟𝑒
The range is an difference between the highest number and the lowest number in the set of numbers.
Example
Work out the mean and range for the numbers given below 1, 3, 6, 7, 9, 4

3. Example
Work out the mean and range for each of the following sets of data a) 1, 3,
17, 15 b) 5, 7, 8, 9,
11, 6, 4, 12 c)
10, 10 d)
18,
21, 24 e)
19,
24, 35

4. Example
The scores below are the clubhouse scores for Olesen during the 2013 Masters, Augusta National. Calculate the mean score for his four rounds. Also find the range for the four results.
Player
Country
Round 1
Round 2
Round 3
Round 4
Total Score
Olesen
Den 78 70 68
284

5. Example
In a game of cricket consisting of 20 overs Sri Lanka beat Kenya with 260 runs.
What is the mean number of runs per over?

6. Example
The table below shows the heights of five of the tallest buildings in the world. What is the mean height of these five buildings?
Building
Height (in metres)
Burj Khalifa
828
Taipei 101
509
Shanghai World Financial Center
492
International Commerce Centre
484
Petronas Tower
452
5 of the tallest buildings