A bar graph is a graph used to display data about different groups. There are all different types of groups that can be looked at. For example the number of different types of bugs in a garden, the number of people with certain eye colours in a class or even the flavours of juice people prefer.
Let's look now at how to create and interpret (understand) column graphs.
Creating a bar graph
Let's say I looked in my garden and I found $6$6 ants, $5$5 worms, $3$3 caterpillars, $1$1 butterfly and $4$4 bees. Watch this video to see how we'd turn this into a bar graph.
Interpreting a bar graph
So what information can we get from a bar graph? Let's watch another video and see.
- Give your graph a heading.
- Label both axes (arms) of the graph.
- Make sure the columns are equal widths and equally spaced.
- Make sure that the height of the column matches the frequency (how often that score occurred).
Worked Examples
Question 1
The table below shows the house points earned by four colour houses at their swimming carnival.
| House | Points |
|---|---|
| Blue | $60$60 |
| Green | $20$20 |
| Yellow | $70$70 |
| Orange | $60$60 |
Complete the graph using the information from the table.
Question 2
The fish shop has $5$5 tanks.
The graph below shows the number of fish in the $5$5 tanks.
Turn this information into a scaled bar graph.
Question 3
A dice is rolled and the number of times it landed on the digits 1-6 is recorded in the table below.
| Dice Number | Number of Rolls |
|---|---|
| 1 | $6$6 |
| 2 | $4$4 |
| 3 | $1$1 |
| 4 | $8$8 |
| 5 | $5$5 |
| 6 | $7$7 |
Complete the graph using the information from the table.
What was the most frequent dice roll?
3
A6
B4
C5
D1
E2
FHow many more 4's were rolled than 2's?
What was the least frequent dice roll?
3
A1
B5
C2
D6
E4
F