Math Puzzle No. 5: The Damsel in Shining Armor

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Long ago, damsels in shining armor battled dragons and rescued knights in distress on a daily basis.  This ultimately lead to the complete extinction of dragons, a major catastrophe for the business of thrilling heroics! Although many of the surviving stories don't stress it, the rescues frequently involved logical thinking and problem-solving.

Once upon a time, a knight was captured by an evil dragon and imprisoned in a castle that was surrounded by a square moat. The moat was infested with extremely hungry and alligators, piranhas, and -- just for good measure -- a few sharks.  The moat was exactly 20 feet across and had no drawbridge or any other means of safely crossing.


After a long time, a damsel appeared, carrying two wooden beams, each 19 feet 8 inches long and 8 inches wide. The beams were strong enough to walk across, but wouldn't reach across the moat.  The knight was despondent.  He'd already waited for weeks to be rescued.  Now he'd have to wait more, until a damsel appeared with longer boards.  (Or perhaps some power tools.)


The damsel, after listening to the knight rant, whine, and throw a decidedly un-knightly tantrum, then rescued the knight using only the beams at her disposal.  How did she do it?




(This problem was adapted from The Heart of Mathematics by Burger and Starbird.)

Scroll down to see the answer to this puzzle!

The previous Math Puzzle and its Solution are available here: https://mathcep.blogspot.com/2020/12/math-puzzle-no-4-hungry-mouse.html





















Solution: 






The previous Math Puzzle and its Solution are available here: https://mathcep.blogspot.com/2020/12/math-puzzle-no-4-hungry-mouse.html





Comments

Krishan said…
Maths is a form of mind game. There are a lot of questions in this that make the mind work hard. I have a blog on How to Solve Your Mastermorphix In Just 6 Easy Steps
January 22, 2023 at 9:51 PM

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