Question

Which pair of ratios form a proportion?

Answer 1

5:8 and 20:32
If you multiply both 5 and 8 by 4 you get 20:32

Answer 2

5:8 and 20:32 would be a proportion.

Easy way to find this:
Set up the proportion as a fraction.
Use the cross product property. Multiply the diagonals and if the products of the diagonals are the same, then they are proportional.