1. Data Data is information
Data handling is when we organise, display and try to understand information.

2. They listened to some songs and timed how long each one lasted
Some children wanted to find out about the length of songs. They wanted to know how long most songs were.
They listened to some songs and timed how long each one lasted

3. 3min 37 seconds 3min 20 seconds 3 min 58 seconds 2 min 58 seconds
Here are their results:
3min 37 seconds
3 min 58 seconds
1 min 45 seconds
3 min 0 seconds
3 min 13 seconds
2 min 35 seconds
3 min 17 seconds
3min 20 seconds
2 min 58 seconds
3 min 12 seconds
1 min 59 seconds
4 min 03 seconds
2 min 15 seconds
3 min 32 seconds

4. Not very easy to understand is it?
Let’s turn it into a graph...

5. Graph showing how many songs there were of each length
Oh dear.... That wasn’t much help
Number of songs
Length (in minutes)

6. Every song is different...
So how can we find out what sort of length is most common?
We can group the data
We’ll start by sorting it into a
tally chart

7. 3min 20 seconds 2 min 58 seconds 3 min 12 seconds 1 min 59 seconds
Song length
Number of songs
1 min 30 sec to
1 min 59 sec
2 min 0 sec to
2 min 29 sec
2 min 30 sec to
2 min 59 sec
3 min 0 sec to
3 min 29 sec
3 min 30 sec to
3 min 59 sec
4 min 0 sec to
4 min 29 sec
4 min 30 sec to
4 min 59 sec
3min 37 seconds
3 min 58 seconds
1 min 45 seconds
3 min 0 seconds
3 min 13 seconds
2 min 35 seconds
3 min 17 seconds

8. Remember how we tally in fives:
So how many does this tally show? 18

9. Right, let’s get back to that tally chart...
... and change it into a frequency table

10. Frequency table Tally chart 2 1 5 3 Song length Number of songs
1 min 30 sec to
1 min 59 sec
2 min 0 sec to
2 min 29 sec
2 min 30 sec to
2 min 59 sec
3 min 0 sec to
3 min 29 sec
3 min 30 sec to
3 min 59 sec
4 min 0 sec to
4 min 29 sec
4 min 30 sec to
4 min 59 sec
Song length
Number of songs
1 min 30 sec to
1 min 59 sec 2
2 min 0 sec to
2 min 29 sec 1
2 min 30 sec to
2 min 59 sec
3 min 0 sec to
3 min 29 sec 5
3 min 30 sec to
3 min 59 sec 3
4 min 0 sec to
4 min 29 sec
4 min 30 sec to
4 min 59 sec

11. Well, that bit was easy!
Now let’s display the information in a pictogram

12. We’re going to use one CD to stand for 2 songs, like this:
Song length
Number of songs
1 min 30 sec to
1 min 59 sec 2
2 min 0 sec to
2 min 29 sec 1
2 min 30 sec to
2 min 59 sec
3 min 0 sec to
3 min 29 sec 5
3 min 30 sec to
3 min 59 sec 3
4 min 0 sec to
4 min 29 sec

13. Now we can use those symbols to make a pictogram
1 min 30 sec to
1 min 59 sec
2 min 0 sec to
2 min 29 sec
2 min 30 sec to
2 min 59 sec
3 min 0 sec to
3 min 29 sec
3 min 30 sec to
3 min 59 sec
4 min 0 sec to
4 min 29 sec
What else do we need?
Song length
= 2 songs
Number of songs

14. We can show the same information in a graph:
1 min 30 to
1 min 59
2 min to
2 min 29
2 min 30 to
2 min 59
3 min 0 to
3 min 29
3 min 30 to
3 min 59
4 min 0 to
4 min 29
Which length of song is the most common?
We can show the same information in a graph: 8 6 4
Number of songs 2
This is called the mode
3 min to
3 min 29 sec
Song length

15. Most songs are between 3 and 4 minutes long.
1 min 30 to
1 min 59
2 min to
2 min 29
2 min 30 to
2 min 59
3 min 0 to
3 min 29
3 min 30 to
3 min 59
4 min 0 to
4 min 29
True or false?
Most songs are between 3 and 4 minutes long. 8 6 4
Number of songs 2
True
Song length

16. The same rule applies to any grouped data.
Grouping data
When you group data, you have to make all the groups equal.
In this example, all the groups were 30 seconds long.
The same rule applies to any grouped data.
If we were grouping tables test scores, we could use:
0-10, , 21-30, and so on.

17. What have we learned? How to group data How to make a tally chart
How to make a frequency table
How to make a pictogram
How to make a graph (bar chart)