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Guest Message by DevFuse
 

bubbled

Member Since 02 May 2013
Offline Last Active Jul 19 2014 08:35 PM
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Posts I've Made

In Topic: "let's make a deal" Marbles

09 June 2014 - 08:11 AM

 

 

 

 

you are a contestant on a game show competing against another person. There are four jars each containing 20 marbles.  At the start, one jar has all blue marbles, another has only green marbles, a third has white marbles, and the last has black marbles.  You see which jar has which at the beginning (the other contestant does not).
 
You may redistribute the marbles however you like except three conditions must persist:
  • every jar must contain at least 1 marble,
  • every marble must be in a jar,
  • no jar may contain more than 50 marbles.  

Once the redistribution occurs, you and the other person will be blindfolded and jars shuffled and randomly placed on the table.  They will pick one jar first then you will pick one from the remaining three.  The marbles in each jar are then counted and scored according to their values:

  • blue = 1
  • green = 3
  • white = 5
  • black = 10

Two questions:

  1. What would be the best configuration of marbles that would most help assist you in winning?
  2. What is the probability you would win this game?

 

The solution contains the assumption:

 

I'm assuming that during the redistribution phase, I will know whether my opponent chose jar 1, 2, 3 or 4.

 

I am trying to reconcile that with the red portion of the OP

 

 

I was with you as to there being no way to gain an advantage until BMAD added this to the terms of the problem:

 

After the first person chooses, you have the option to redistribute the marbles again.

 

Given, that you get to redistribute the marbles, it is reasonable to assume you can tell which jar was chosen and then act accordingly.

 

 


I did leave this part out, you are only blindfolded after the first person picks their jar and then the jars are shuffled again while you are blindfolded.

The jars are not transparent

 

 

With this order of events:

  1. I fill the jars the way I want them
  2. Because the jars are not transparent my opponent has no clue about their contents
  3. My opponent picks one
  4. I know which one he picked, either because I was watching
    or because I now have access to all the remaining jars and marbles.
  5. I re-fill the jars the way I want them.
  6. I am blindfolded
  7. The jars are shuffled
  8. I pick one, while blindfolded

there is a strategy.

 

Yes. Your breakdown is exactly how I interpreted the problem after the clarifications. Do you disagree with my strategy?


In Topic: "let's make a deal" Marbles

08 June 2014 - 11:45 AM

 

 

you are a contestant on a game show competing against another person. There are four jars each containing 20 marbles.  At the start, one jar has all blue marbles, another has only green marbles, a third has white marbles, and the last has black marbles.  You see which jar has which at the beginning (the other contestant does not).
 
You may redistribute the marbles however you like except three conditions must persist:
  • every jar must contain at least 1 marble,
  • every marble must be in a jar,
  • no jar may contain more than 50 marbles.  

Once the redistribution occurs, you and the other person will be blindfolded and jars shuffled and randomly placed on the table.  They will pick one jar first then you will pick one from the remaining three.  The marbles in each jar are then counted and scored according to their values:

  • blue = 1
  • green = 3
  • white = 5
  • black = 10

Two questions:

  1. What would be the best configuration of marbles that would most help assist you in winning?
  2. What is the probability you would win this game?

 

 

 

The solution contains the assumption:

 

I'm assuming that during the redistribution phase, I will know whether my opponent chose jar 1, 2, 3 or 4.

 

I am trying to reconcile that with the red portion of the OP

 

I was with you as to there being no way to gain an advantage until BMAD added this to the terms of the problem:

 

After the first person chooses, you have the option to redistribute the marbles again.

 

Given, that you get to redistribute the marbles, it is reasonable to assume you can tell which jar was chosen and then act accordingly.


In Topic: Wagon Spokes

24 May 2014 - 08:11 AM

If a wagon wheel had 10 more spokes, the angle between the spokes would decrease by 6 degrees. How many spokes does the wheel have? 

 

 

Spoiler for looks like


In Topic: I love a parade. But how long is it?

23 May 2014 - 12:10 PM

Rainman and BMAD were out for a walk the other day when they came across some barracades along a parade route that blocked their path.
 
So much for that, mused BMAD, it looks like we either turn back or wait to watch a parade.
 
I've got a puzzle idea, replied Rainman. Let's measure how long the parade is. When it arrives, you start walking slowly alongside it, and I'll do the same, but in the opposite direction. When I get to the end of the parade I'll stop. When the end of the parade catches up to you, you call my cell phone. BMAD agreed.
 
When BMAD made the call, she had walked 12 blocks. Rainman reported that he had walked only a third as many. Assuming all speeds were constant, and Rainman and BMAD's speeds were the same, how long was the parade?

 

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Spoiler for seems like
 


In Topic: The innocent man - lateral quickie

21 May 2014 - 12:07 PM

A man who was born before his father killed his mother and then married his sister. Yet he was guilty of no wrongdoing. How is this possible?

 

Spoiler for maybe?