Weekly Riddle #2
Ferraris and Goats
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WinCustomize Forums
WinCustomize Forums
This riddle/annoying problem, as I'm sure most of you have seen/heard before, is definitely one of my favorite. So, here it is:
Imagine you were taking part in a game show. You've won through to the last round, which is a game of chance. There are three doors - all you have to do is to choose which door you want to open - Door 1, Door 2 or Door 3. Behind one door is a Ferrari. Behind each of the other two is a goat. Let's assume that you are normal enough to want a Ferrari.
After a moment's indecision you plump for a door - let's say it's Door 2. The gameshow host nods, knowingly. "Okay," he says, "I'm going to give you a final chance to change your mind. And I'm even going to help you." He opens Door 3 and shows you there's a goat behind it. "Now," says the host, "do you want to stick with the door you chose, or do you want to change to another door."
The question I ask you is subtly different. Should you stick with the door you chose, should you change (presumably to Door 1), or doesn't it matter in probability terms whether you stick or change?
Those of you who know the answer, please don't cheat. I HATE cheaters. Those of you who have never heard of this problem, guess as you wish. I will post the correct answer and solution as soon as someone guesses wrong. Happy Thinking
Imagine you were taking part in a game show. You've won through to the last round, which is a game of chance. There are three doors - all you have to do is to choose which door you want to open - Door 1, Door 2 or Door 3. Behind one door is a Ferrari. Behind each of the other two is a goat. Let's assume that you are normal enough to want a Ferrari.
After a moment's indecision you plump for a door - let's say it's Door 2. The gameshow host nods, knowingly. "Okay," he says, "I'm going to give you a final chance to change your mind. And I'm even going to help you." He opens Door 3 and shows you there's a goat behind it. "Now," says the host, "do you want to stick with the door you chose, or do you want to change to another door."
The question I ask you is subtly different. Should you stick with the door you chose, should you change (presumably to Door 1), or doesn't it matter in probability terms whether you stick or change?
Those of you who know the answer, please don't cheat. I HATE cheaters. Those of you who have never heard of this problem, guess as you wish. I will post the correct answer and solution as soon as someone guesses wrong. Happy Thinking
