Bilkent IEEE Weekly Puzzle

30 October 2013 Comments Off on Bilkent IEEE Weekly Puzzle

#5 – Two Balls

Two balls, each either black or red, are placed in a bag. You draw a ball from the bag, which contains at least one red ball. If the ball you draw is red, what is the probability that the ball remaining in the bag is red too?

The Prize for This Question: Rubik’s Race

The Winner of Puzzle #3: Umar Raza

Send your answer to by 5:30 p.m. on November 5, or visit to submit your answer online, and get a chance to win the prize!

This question was prepared by Emrehan Halıcı, president of the Turkey Intelligence Foundation, for Bilkent IEEE.