The scale on different number lines can be different. Look at these two number lines: On this one, the intervals represent gaps of 100. And on this one, the intervals represent gaps of 200.

Understand that one number can have several factor pairs – for example, 3 and 4 are factors of 12 (3 x 4 = 12), and so are 2 and 6 (2 x 6 = 12), and 1 and 12 (1 x 12 = 12).

For example, to find out the halfway number on this number line, you find the difference between 1500 and 500. 1500 − 500 = 1000 Then halve it. 1000 ÷ 2 = 500 Now you can add 500 to the start ...