Cool Math Problem

[susy_gwen]

So, I gave my geometry question yesterday, but didn't find the solution until this morning. And it's not what I was expecting. Because it's so interesting, I'd thought I'd challenge all of you with it. I'll post the answer tonight. So, have fun and enjoy!

Who Shook Who’s Hand?The Bakers had a barbeque in their back yard. They invited three

Comments

[angua9]

What a fun question!

As best I can tell, Mrs. Baker shook hands with four friends:

• the one who shook hands with 6,
  
• the one who shook hands with 5,
  
• the one who shook hands with 4, and
  
• the one who shook hands with 3.
  

I'd have to show you my little diagram to show how I know this is correct.

[specner]

My wife, jiminyc, passed this on to me. I got a different answer than Angua, and here is how I figured it. Sorry it's elaborate, but this is an elaborate problem! I do agree that this is a fun question...have you guys tried Sudoku? I'm totally addicted! It's a pure logic puzzle involving the numbers 1-9 but no actual math. USA Today has a daily puzzle at http://puzzles.usatoday.com/sudoku/... )

[jiminyc]

*points to above post*

Whether he's right or not, I think you can clearly see why we made the agreement early on in our marriage that HE does all the taxes and I have all the babies. :)

[angua9]

Yeah, I agree that it's three. I miscounted a line in my diagram. :(

[sannalim]

I saw angua9's answer (sans diagram) already, but haven't looked at any of the other comments that came in while I was working on my answer. I'm afraid I must beg to differ with our esteemed Queen ORX and say that the answer is THREE.

* No-one shook hands with Mr B because he was at the grill finishing the hamburgers. For all intents and purposes, we can pretend he doesn't exist.

* Each of the six visitors shook hands a different number of times, but nothing in the wording of the question prevents Mrs B from having shaken hands the same number of times as one of her guests.

* Mrs B plus six guests makes seven. It's silly to think of shaking your own hand, so the maximum number of handshakes one person could have made is N - 1 = 6. Theoretically one of the guests could have been very antisocial that evening and given zero handshakes, in which case the maximum possible number of handshakes is five

[stmarysalice]

My answer is: Mrs. Baker shook hands once.

How I figure it: The question asks how many times Mrs. Baker shook hands, not how many hands did she shake?