A tractor has 8 forward speeds. The speed ratio varies in exact geometrical progressions. If the speed ratio in highest and lowest gear are 14.9:1 and 108:1, the geometrical constant will be __________

(a) 0.328

(b) 1.328

(c) 2.328

(d) 3.328

The question was posed to me by my school principal while I was bunking the class.

Question is taken from Mechanical Power Transmission topic in division Mechanical Power Transmission of Farm Machinery