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Red / Blue Marbles

OK, that works however if you add 50% blue to bottom of one and same to the other bottle, and cover w/ the red marbles proportionately you have 100% chance in both bottles of picking a red marble

Nasty Quaker
Wednesday, January 2, 2002

The problem description states you must pick both a jar and a marble randomly.  This means you can't stack the jars and pick only from the top.

Nice try.

Chad Hulbert
Wednesday, January 2, 2002

I'm not sure what the question is...but if it's the same red/blue,white marble question I had when interviewing with intel...I know the answer.

Is it you have three with red marbles, one with blue marbles, and one with a mixture of red and blue marbles? The labels on the can are incorrect and you have one pick and then you have to determine which can gets which label.

Is this the question?  If it is, I have the correct answer.  Someone let me know.

hollie welcher
Monday, January 28, 2002

I got the problem statement confused; I somehow thought that each jar held 50 marbles; that means you can't get all the marbles in jars unless you fill both jars; guess what arrangement is best in this case?

Daniel Boyd
Wednesday, February 6, 2002

mmm, nowhere does the question imply a maximal capacity for either jar. It does, however, state:

" can arrange the marbles however you like..."

And that means to me that you _can_ "stack" the marbles & get a 100% chance of a picking a red - with a lot less math ;p

Saturday, March 16, 2002

Jar 1: 1 Red.
Jar 2: 49 Red, 50 Blue
Is this correct?

Monday, April 29, 2002

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