What are the minimum member of bits required to distinguish 108 distinct objects?

Question

This is a question in a book written by reputed author RP Jain named Modern Digital Electronics where he answers the above as 8 but whereas simple logic tells 128 distinct objects can be distinguished just by 7 bits.

Then why is the answer 8 bits?

Answer 1

usually electronic devices have bits in powers of 2, thus 2 , 4, 8, 16, 32, and 64 bits. You cannot have a 7 bit machine. You are true that $2^7 = 128$ can do it. Bur the problem there is no 7-bit electronic device, the closest to your answer is thus 8-bit