A Book has 1257 digits in it page numbers.
How many pages does the book have?

Each page from 10 to 99, inclusive (so total of 90 pages) needs two digits (for example page 12 needs two digits: 1 and 2); Each page from 100 to 200, inclusive (so total of 101 pages) needs three digits (for example page 123 needs three digits: 1, 2 and 3)