The message occupies 6 pages of 40 lines, each line contains 60 characters. The information volume of the entire message

The message occupies 6 pages of 40 lines, each line contains 60 characters. The information volume of the entire message is 9000 bytes. How many characters are in the alphabet of the language in which this message is written.

The volume of this message can be found by the formula I = n (pages) * n (lines) * n (characters per line) * i, where I is the volume of the entire message, and i is the informational weight of one character.
Substitute all known values into this equality.
9000 bytes = 6 * 40 * 60 * i.
Let’s find the value of the variable i.
i = 9000 bytes / (6 * 40 * 60) = 72000 bits / (6 * 40 * 60) = 72000/14400 = 5 bits.
The cardinality of the alphabet N is 2 ^ i, that is, N = 2 ^ 5 = 32.
Answer: 32 characters.