I have a number of the form abcd. How many digits does it have?
There are 4 digits, each of which is represented by letters of alphabet a, b, c and d.
A librarian used 2893 digits to number the pages of a book. How many pages does the book have?
If a 3 digit number 'abc' has 3 factors, how many factors does the 6-digit number 'abcabc' have?