The task goes as follows.
When we get our drivers-permit we learn that the braking length grows proportional to the speed squared. (If we double the speed, the braking distance is quadrupled. Assume that the road is leveled and that the braking force is constant.)
When two quantities are proportional I thought that implies that if you divide the first quantity with the other you should get roughly the same number for different numbers. The expression under should be a constant.
Is this interpretation correct?