Challenge question #36 (07/11/2016)
In numbering the pages of a book, $408$ digits were used. How many pages does the book have?
The book has $172$ pages.Worked Solution
The next $90$ pages contain $2$ digits each.
Suppose the book has $n$ pages containing $3$ digits each.
$\approx 68.6\%$ of the sector is occupied by the inner circle.Worked Solution