Like this presentation? Why not share!

# Handling Data 2

## on Oct 22, 2009

• 1,145 views

### Views

Total Views
1,145
Views on SlideShare
1,144
Embed Views
1

Likes
0
4
0

### 1 Embed1

 http://www.slideshare.net 1

### Report content

• Comment goes here.
Are you sure you want to

## Handling Data 2Presentation Transcript

• Handling data 2
BTEOTSSSBAT:
Calculate the mean, mode, median and range of a set of data
Find the mean from a frequency table
• Key words
Mean
Median
Mode
Range
Frequency
• Mean, median and mode
There are three types of average: mean, mode and median.
Mode
This is the one that occurs the most.
Median
This is the one in the middle, when all the numbers have been put into numerical order.
Mean
This is the one that we normally think of when we are asked to find the average.
Mean = Total of the scores
No of scores
• Range
The range is also an important piece of information. It tells us how spread out the information is.
Range = largest – smallest
• Example
Here are the scores that 5 people get for a test.
6 7 5 6 6
Find (a) the mean (b) the mode and (c) the median score and (d) the range
(a) Mean = 6 + 7 + 5 + 6 + 6 = 30
5 5
= 6
(b) Mode: 6 occurs the most (3 times) so the mode is 6
(c) Median
Step 1: put in numerical order: 5, 6, 6, 6, 7
Step 2: identify the middle number: 5, 6, 6, 6, 7
So the median is 6.
(d) The range is 7 – 5 = 2.
• Now try these 1
Five other people take the same test and their scores are:
5 3 5 5 7
Find (a) the mean (b) the mode (c) the median score and (d) the range
The following are the midday temperatures over a week:
23 C 24C 25C 26C 20C 23C 27C
Find (a) the mean (b) the mode (c) the median score and (d) the range
• Using frequency tables
If we survey 120 houses and asked how many people under the age of 16 lived in the house, we might get the following results:
Range
= 6-0 = 6
Highest frequency = mode
Mode = 0
• 37  0 = 0
23  1 = 23
1.51 children
The mean number of children per house would then be
• Now try these 2
1 .The number of children per family on a housing estate were recorded as follows:
Find (a) the range (b) the mode and (c) the mean number of children per family.
• 2. An agricultural researcher counted the number of peas in a pod in a certain strain as follows:
Find (a) the range (b) the mode and (c) the mean number of children per family.