Puzzle/Paradox..
Easy question for everyone here I am sure.
I saw this somewhere and I have a question, but it is different from the one asked in the puzzle I saw.
Box A
$100 + $100
Box B
$100 + $1
Ok. So you are presented with two identical boxes and told that you can reach in and grab one of the two bills from a box. You are told that in Box A there are two $100 bills and in Box B there is a $100 bill and a $1 bill. You are not told which is Box A or B.
You are going to get two turns to pick, so we won’t even go through the scenario where you pick the $1 bill first, as no matter which box you pick from you will get a $100 bill with your second pick.
But, how about if you pick a $100 bill on your first pick. Is there a strategy for picking a box that will give you a greater chance of getting another $100?
-If you picked from box A there is a 100 % chance of getting another $100 if you pick box A again.
-If you picked from box B there is a 0% chance to get $100 if you pick from box B again.
That said, the very fact that you pulled a $100 bill on your first pick makes it twice as likely that you picked box A, and thus you should pick from that same box again. Or does it?
Should you pick from the same box again? It seems like a yes to me.
3 Replies
Yes
The odds are 2/3 that you picked from box a and 1/3 you picked from box b so you should stay with the same box
What Nich said
This is just a variant of Monty Hall
The presenter claimed it to be a variant of Bertrand's Box Paradox, but is set up differently. In the example I saw the creator seemed to conflate the decisions points imo. They were interchanging the choice of boxes (of which there were 2) with the choice of bills (of which there were 4) and came to incorrect conclusion that it did not matter which box you chose if you first picked a $100. Which, of course, is incorrect.
It seemed wrong to me so that is why I posted.