**1. The problem statement, all variables and given/known data**
A ramp system is set up. Due to friction the ramp has an efficiency of 82%. Two cars of equal mass are allowed to collide and car 1 starts from rest at height h1. The two stick together and coast to a height of h2. Derive a formula relating h1 to h2.

**2. Relevant equations**
I=Δp, p=m*v, eff=(output/input)*100%, GPE=mgh,

**3. The attempt at a solution**
Unfortunately, I cannot figure out almost anything based on this question. Even my friend's father, who is an engineer, could not understand. Just looking for some good help if any one is available.