2008 Mock ARML 1 Problems/Problem 4
Problem
There are 
black balls and 
white ball in a hat. A turn consists of picking a ball from the hat and replacing it with one of the opposite color. Compute the probability that, after a sequence of turns, there are 
black balls in the hat before there are white balls.
Solution
This problem needs a solution. If you have a solution for it, please help us out by adding it. The answer is 
.
See also
| 2008 Mock ARML 1 (Problems, Source) | ||
| Preceded by Problem 3 |
Followed by Problem 5 | |
| 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 | ||
