Number line 1 is one of the first skills recommended (along with) when beginning to use Khan Academy, being one of the few that is not linked to from the start. The first instance of this exercise is in the 3rd grade (U.S.) Math Mission.

Types of Problems

This exercise only has one type of problem:

  1. The Number line: this type of problem requires the user to drag an orange dot with the mouse to positions between 0 and 20 on the number line.


  1. User can position the dot between intervals to be considered a decimal or fraction.
  2. The problem gives users the scale, all they need to do is count.

Real-life Applications

  1. Knowing how to count is essential for learning algebra and the higher maths, and counting is used for almost everything humans do.