Gear Ratio = (Driving Gear Teeth):(Driven Gear Teeth)
Gear Reduction = Driven Gear Teeth / Driving Gear Teeth
Output Torque = Input Torque x Gear Reduction
Gear Reduction Required = Output Torque / Input Torque
Output Speed = Input Speed / Gear Reduction
Gear Reduction Required = Input Speed / Output Speed
Compound Gear Reduction = Gear Reduction 1 x Gear Reduction 2 x Gear Reduction 3 x (all other gear reductions)