Efficiency of an inclined plane if a body with a mass of 150 kg is lifted along an inclined plane to a height of 1.5 m

Efficiency of an inclined plane if a body with a mass of 150 kg is lifted along an inclined plane to a height of 1.5 m by acting with a force of 900 N. The length of an inclined plane is 4 m

Efficiency is determined from the ratio of useful work to the work done:
k = (A1 / A2) * 100%;
Useful work A1 = m * g * h and
Work done A2 = F * S,
Where
m = 150kg,
g = 10m / s ^ 2 – acceleration of gravity,
h = 1.5m,
F = 900H,
S = 4m;
k = (2250J / 3600J) * 100% = 62.5%.