Is for over two and 20/6 proportions

No they're not proportional, and it's four*.
4/2 = 2
20/6 = 3.333333333334 or 3 1/3

To find out if fractions are proportional you cross multiply.

4       20
--  x   ---
2        6

4 x 6 = 24

2 x 20 = 40

If they are alike then they are proportional, if they are not then they are NOT proportional.