Can you solve the stolen rubies riddle? - Dennis Shasha
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Townspeople are demanding that a corrupt merchant’s collection of 30 rubies be confiscated to reimburse the victims of his schemes. The king announces that the fine will be determined through a game of wits between the merchant and the king’s most clever advisor – you. Can you outfox the merchant and win back the greatest amount of rubies to help his victims? Dennis Shasha shows how.
(Two-pass) Sometimes the best way to dig into a problem is to change the rules. Because of the king’s love of the number two, he decides to allow you two passes. The scoundrel must still conform to the king’s rules regarding 6 more rubies in one box than another and at least two rubies per box. However, you get two cracks at the rubies. You are allowed to lay down your cards as before and receive the rubies from each box if you don’t ask for too many. However, you do not see how many are left or how many were in the boxes from which you asked. Then you get to do this again. For example, suppose you ask for 8 rubies from all three boxes during the first pass and you receive eight from the first and third boxes but nothing from the middle one. In the second pass, you might ask for two rubies from the middle box (because it has to have at least that many) and four from the other two. You are guaranteed to get at least four in total from those other two. So your total would be at least 16+2+4 rubies over the two passes. Can you think of a strategy that yields you more rubies?
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Meet The Creators
- Educator Dennis Shasha
- Director Milos Zivkov
- Narrator Addison Anderson
- Illustrator Stevica Zivkov
- Animator Milos Zivkov
- Character Designer Milos Zivkov
- Content Producer Gerta Xhelo
- Editorial Producer Alex Rosenthal
- Associate Producer Bethany Cutmore-Scott
- Fact-Checker Brian Gutierrez