Question

If log 2 = 0.30103, the number of digits in 264 is:
A. 18 B. 19
C. 20 D. 21

Answer 1

It should be $2^{64}$

Let x = $2^{64}$

Log x = $log 2^{64}$ 

Logx = 64(log2)

logx = 64(0.30103)

logx = 19.26592

The characteristic of x is 19
Therefore, there are 20 (19+1) digits in  $2^{64}$