Åk 6–9
2.4 Numbers on the Number Line 
All numbers can be shown on the number axis which is normally called the number line.

A normal number line which is used in real life is a tape measure.

In mathematics we normally show the number line horizontally.  Below shows a number line where whole numbers in the area of 0 to 10 are marked.

It is important to have the same distance between the marks we make when we draw a number line.

The arrow to the far right on the number line shows which direction the numbers increase in numerical order.

Example A

Show the numbers 2 and 7 on the number line.

When we draw the number line, we need to first think about which area is appropriate and in this example it is appropriate to choose the area from 0 to 10 because both the numbers (2 and 7) are there.

Example B 

Show the numbers 2, 7, and 74 on the number line.

The appropriate area in this example would be from 0 to 100 because all three numbers (2, 7, and 74) are in this area.  On the following number line, the tens are marked.