Please help

The force F needed to tighten a blot varies as the length L of the wrench handle.
If F=250N for L = 22cm, and F=550 N for L = 10cm, determine the equation relating F and L.

 

F = kl

250 = k/ (22)

k = 250*22 =  5500

 

F = (5500) / L   Newtons