From information given, there are two forces in action, the vertical and the horizontal. We first need to calculate separately work done by these two forces, then determine the efficiency.
Work = Force × distance
work(a) → 600N × 2m = 1,200 Nm
work(b) → 300N × 5m = 1,500 Nm
Efficiency = work(a) / work (b) × 100
Efficiency = 1200 / 1500 × 100
Efficiency = 0.8 × 100
Efficiency = 80%
Therefore the efficiency of the ramp is 80%
