Efficiency = M.AV.R\frac{\text{M.A}}{\text{V.R}}V.RM.A x 100
M.A = LOADEFFORT\frac{\text{LOAD}}{\text{EFFORT}}EFFORTLOAD
V.R = 2, Eff. = 60% = 0.6, Load = 300N
0.6 = M.A2\frac{\text{M.A}}{2}2M.A
M.A = 1.2
1.2 = 300E\frac{300}{\text{E}}E300
Effort = 3001.2\frac{300}{1.2}1.2300 = 250N
