For a bevel gear having the pitch angle θ, the ratio of formative number of teeth (TE) to actual number of teeth (T) is

(a) 1/sin θ

(b) 1/cos θ

(c) 1/tan θ

(d) sin θ cos θ

The question was posed to me in an internship interview.

This interesting question is from Worm Gears topic in chapter Toothed Gearing & Gear Trains of Machine Kinematics