Between each of the integers, 0, 1, 2, 3, etc., the space is divided into 6 units. We can use this to our advantage.
Since 1/2 = 2/4 = 5/10 = 3/6 = ....., thus:
2 1/2 = 2 3/6. Now we can easily plot points on the number line.
2 3/6 = 2 units and 3 sub units.
1 5/6 = 1 unit and 5 sub units
Check the attached image to see the graphical solution of the question!
Hope that helps!