Medium
If the digit 1 occurs 130 times on writing all page numbers of a book starting from 1, then how many pages are there in the book?
Explanation
Explanation
Counting occurrences of digit '1' from 1 to 190 pages gives exactly 130 occurrences (accounting for units, tens, and hundreds place appearances), so the book has 190 pages.
PRO TIP
Re-check your working by substituting the answer back into the original question.