Here is the Riddle from Monday.
Answer from Car Talk
The answer is $13.50. All that was damaged was volume 2, which is the volume in the middle. You have volume 1 sitting on the shelf to the left. Volume 2 is next to it on the right. And volume 3 is even further to the right.The riddle is somewhat flawed unless the actual collection of books really has printing on both sides of every page in the 2500 total pages per book. I highly doubt it. Further still, the fact that you could actually clean both sides of the page leaves me a little suspicious. It would probably be easier to just find a replacement for Volume 2 altogether.
Now remember, as the writer said, when he reached for them on the shelf he could see that mold had damaged every page and cover from the front of volume 1, though that cover was undamaged, to the back cover of volume 3, though that too was undamaged. So as the books are placed on the shelf, the cover of volume 1 is the closest thing of volume 1 to volume 2.
So if you go to your bookshelf and look at three books and imagine they're labeled volume 1, volume 2, volume 3, you'll see that the book in the middle is the only one that was damaged by the mold, and there were two covers damaged. Right? Those two covers, the front and back cover of volume 2.
And the reason it was $13.50 was that even though there were 2500 printed pages, there were only 1250 pages of actual paper, because there's printing on both sides. So it's only a penny apiece to clean each page. And two covers, right, 50 cents apiece, $13.50.
Stay tuned for another Riddle. This one will either be deceptively simple or a real nugget scratcher.