An easy one! At least, that's how it's classified where I found it over at
http://www.folj.com/puzzles/easy.htm.
A pot contains 75 white beans and 150 black ones. Next to the pot is a pile of 300 black beans.
A somewhat demented chef takes the beans from the pot in the following manner:
- He takes two beans at random from the pot.
- If one of the beans is black, he places it in the pile of black beans and puts the other one (white or black) back in the pot.
- Otherwise, he throws both beans away and takes a black bean from the pile and puts it into the pot.
Note that two beans have been taken out and only one put back. He repeats the procedure, reducing the number of beans in the pot by one each time, until there is only one bean in the pot.
What colour bean is the last one in the pot?
[Oh - and please enclose answers in spoiler tags as usual. Thanks!]