Question: There are three books on a shelf standing side by side. Each book is 10ml thick. The bookworm eats its way through the first page of the first book to the last page of the last book. How far did the bookworm move if it can only move in a straight horizontal line?
Answer: The book worm only moved 10ml because the first page of the first book will be next to the middle book and the last page of the last book will also be next to the middle book. The bookworm eats through only one book, each book is 10ml so therefore the bookworm moves only 10ml.