Daily Brain Games (Mar 15) - how witty are you?
There are six cards on the table (faces down). We know that two of them (and ONLY two) are Kings, but we do not know where they are. Let's imagine that you pick two cards randomly and turn them. Tell me, which is more probable:
- that at least one of them will be a King; or
- there won't be any Kings among them.
Why? How did you come up with the solution?
Please don't tell me that you were just guessing because I will not accept that! :-)))))
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The more probable is: One of them will be king.
Out of the 6 cards, we can draw 2 cards in 15 different ways: 6!/[2!x(6-2)!]=15
Out of this 15 different draws, only 6 won't contain any Kings: 4x3/2=6; and 9 will contain at least one King.
This is the correct answer, congratulations!
Reward is on the way...
Thank you! :)
You are welcome :-)
You got a 12.50% upvote from @luckyvotes courtesy of @ksolymosi!
The previous guy is probably correct already .. ?
In the long run -"that at least one of them will be a King"
But the way I would think of it is that - Initially the Chances are 1 in 3 (2 out of 6) , and IF the King hasn't yet been drawn, there is a 2 out of 5 chance to hit the king .. but yes - previous guy seems to be more clinical with his calculation. I would have said then you add the 2 together giving 0.3333 + 0.4 = 0.7333 or 73.333% chance of hitting a King .. Let me know if I'm close ...
Lol - I could be So wrong heheheh
Well, there are 15 different draws out of which 9 has Kings in it, so - provided that you have equal chance to draw any of them - you will have a 3:5 chance to have a King in your draw. :-)))
So, close enough? :-)))
Anyway, thanks for participating! Have a nice day!
Yes, I am 100% with you .. that works to a 60% chance of atleast hitting a King. I was in a rush to leave so I came up with some other random answer lol
Knew it was slightly off as I sent it, but it was fun :))
Thanks for visiting! :-)
The possibility is pretty high that at least one that is flipped will be a king, but a slightly better chance there won’t be.
Here’s why:
The first card you flip you have a 1/3 (33.33%) chance of a king and 2/3 chance of not flipping it.
The second card you flip, the chances increase if the first one was not a king to 2/5 (40%) and 3/5 (60%) chance of not getting a king.
The probability of not getting a king is higher.
Well, your arguments look good, but there is a slight misunderstanding. It says above that
which means, that you pick two cards and not one plus one.
So @cryptobserver is the winner today.
Thanks for participating anyway!
Ah. Ok. I’ll try again tomorrow.
Good puzzle today. Thanks.
Thank you! Seeya!