A bar chart trades numbers for heights
Taller bar, bigger number. To read one, follow the top of the bar across to the scale on the side — and check what one step of the scale is worth first.
Class 3 to 11 · 47 games
Data and graphs, explained with pictures
Reading numbers off a chart, and finding the middle of a set of numbers.
In everyday life: A chart of rainfall by month, run scores in a match, marks for the whole class.
The mean is what everyone would get if you shared it out equally
Add up all the values, then divide by how many there are. It is the one number that stands in for the whole group.
A worked example
Four students scored 6, 8, 10 and 8. What is the mean?
8
6 + 8 + 10 + 8 makes 32, and 32 shared between 4 students is 8 each.
Words to know
- scale
- What one step on the axis of a chart is worth.
- mean
- The average — the total shared equally between all the values.
In the games
You will read totals off bar charts and find the mean of a small set of values.
Skills
- Read a bar chart · Class 4
- Mean of a data set · Class 7
- Median, mode and range · Class 7
- Mean and median of grouped data · Class 10
- Range, mean deviation and variance · Class 11
By class
Class 3 data and graphs (2) · Class 4 data and graphs (4) · Class 5 data and graphs (3) · Class 6 data and graphs (3) · Class 7 data and graphs (14) · Class 8 data and graphs (7) · Class 9 data and graphs (2) · Class 10 data and graphs (6) · Class 11 data and graphs (6)
Practise data and graphs in Tivumo
No download, no account for your child. Classes 3 to 12, more than 1,000 games.