What digit will used most?

Answer 1

According to Benford's law, the first digit is most likely to be 1.

Benford's law for the first digit states that the probability of digit, d, is

log10(1 + 1/d) where d = 1, 2, ... , 9. [0 cannot be the leading digit].

This gives the probability of 1 as 30.1%.

The distribution becomes more uniform as the number of digits in the representation of numbers is increased but since we usually truncate numbers to a few digits, the state of uniformity is not always reached.