All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Probability
Four balls (Posted on 2017-05-19) Difficulty: 2 of 5
There are four balls in a hat: a blue one, a white one, and two red ones. Now I draw simultaneously two balls, look at them, and announce that at least one of them is red.

What is the chance that the other is red as well?

See The Solution Submitted by Ady TZIDON    
Rating: 3.5000 (2 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Hints/Tips There is only one correct answer !....SPOILER | Comment 16 of 22 |
I believe that both sides want to justify their original answers.
Still, reading the text carefully, only .20 qualifies (!).
There was no previous protocol referring the format of
my announcement , no other color was mentioned and on top of that  
 the initial content of 3 colors precludes a question "if there is at least one white marble, what is the chance that the other is white as well?
-  such a question would trigger a quip "No way", not a   "1/3".

In retrospect, the only  fault  in my puzzle was grading it d2.
Mea culpa.

  Posted by Ady TZIDON on 2017-05-22 03:02:19
Please log in:
Remember me:
Sign up! | Forgot password

Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (0)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Copyright © 2002 - 2019 by Animus Pactum Consulting. All rights reserved. Privacy Information