To understand the logic view the mechanism as follows:
First, assume your pivot point at the center of the nut. The torque applied to the nut is the force on the troque wrench handle times the distance from the nut center to the point of applied force. This is L + E. There are no shunt force paths. So T = (L+E) * F.
We do not know the force. But we can determine the force from the torque wrench reading. Y is the reading of the torque wrench. Thus, F = Y / L.
Thus, T = (L+E) * Y / L .
L and E can be in any units so long as both are the same and T will be in the same units as Y.
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