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You probably know the trick in the movie the prestige :

A magician has found an impressive magic trick  : he goes into a machine, close the door, and then disappears and reappears in the other side of the room. But the machine is not perfect : instead of just teleporting him, it duplicates him. The magician stays where he is, and a copy is created at the other side of the room. Then, the magician in the machine falls discreetly in a water tank under the floor and is drowned. Edit: The probability of the new copy of the magician being drowned is 1/2 (in other words, the new copy has 1/2 chances of being drowned, and 1/2 chances of popping into the room). Also, the water tank never fails and the chances are 1 that the magician dropping in the tank dies.

So the magician doesn't really like doing this trick, because "you never know where you are going to be, on the other side of the room or drowned".

Now, the paradox is the following : Imagine the magician does the trick 100 times. What are his chances of surviving ?

Edit, additional question: What are the chances of the magician of keeping his physical brain and not having a new one ?

Quick analysis: One one hand, there is one magician alive, and 100 drowned magicians, so his chances are 1 out of 100.

On the other hand, each time he does the trick, he has 1/2 chances of staying alive, so his chances are $(1/2)^{100}=1/(2^{100})$ of staying alive.

What is the right response and why ?

You probably know the trick in the movie The Prestige :

[MOVIE SPOILER] A magician has found an impressive magic trick: he goes into a machine, close the door, and then disappears and reappears in the other side of the room. But the machine is not perfect : instead of just teleporting him, it duplicates him. The magician stays where he is, and a copy is created at the other side of the room. Then, the magician in the machine falls discreetly in a water tank under the floor and is drowned. Edit: The probability of the new copy of the magician being drowned is 1/2 (in other words, the new copy has 1/2 chances of being drowned, and 1/2 chances of popping into the room). Also, the water tank never fails and the chances are 1 that the magician dropping in the tank dies.

So the magician doesn't really like doing this trick, because "you never know where you are going to be, on the other side of the room or drowned".

Now, the paradox is the following : Imagine the magician does the trick 100 times. What are his chances of surviving ?

Edit, additional question: What are the chances of the magician of keeping his physical brain and not having a new one ?

Quick analysis: One one hand, there is one magician alive, and 100 drowned magicians, so his chances are 1 out of 100.

On the other hand, each time he does the trick, he has 1/2 chances of staying alive, so his chances are $(1/2)^{100}=1/(2^{100})$ of staying alive.

What is the right response and why ?

You probably know the trick in the movie the prestige :

A magician has found an impressive magic trick : he goes into a machine, close the door, and then disappears and reappears in the other side of the room. But the machine is not perfect : instead of just teleporting him, it duplicates him. The magician stays where he is, and a copy is created at the other side of the room. Then, the magician in the machine falls discreetly in a water tank under the floor and is drowned. Edit: The probability of the new copy of the magician being drowned is 1/2 (in other words, the new copy has 1/2 chances of being drowned, and 1/2 chances of popping into the room). Also, the water tank never fails and the chances ar 1 that the magician dropping in the tank dies.

So the magician doesn't really like doing this trick, because "you never know where you are going to be, on the other side of the room or drowned".

Now, the paradox is the following : Imagine the magician does the trick 100 times. What are his chances of surviving ?

Edit, additional question: What are the chances of the magician of keeping his phisical brain and not having a new one ?

Quick analysis: One one hand, there is one magician alive, and 100 drowned magicians, so his chances are 1 out of 100.

On the other hand, each time he does the trick, he has 1/2 chances of staying alive, so his chances are $(1/2)^{100}=1/(2^{100})$ of staying alive.

What is the right response and why ?

You probably know the trick in the movie the prestige :

A magician has found an impressive magic trick : he goes into a machine, close the door, and then disappears and reappears in the other side of the room. But the machine is not perfect : instead of just teleporting him, it duplicates him. The magician stays where he is, and a copy is created at the other side of the room. Then, the magician in the machine falls discreetly in a water tank under the floor and is drowned. Edit: The probability of the new copy of the magician being drowned is 1/2 (in other words, the new copy has 1/2 chances of being drowned, and 1/2 chances of popping into the room). Also, the water tank never fails and the chances are 1 that the magician dropping in the tank dies.

So the magician doesn't really like doing this trick, because "you never know where you are going to be, on the other side of the room or drowned".

Now, the paradox is the following : Imagine the magician does the trick 100 times. What are his chances of surviving ?

Edit, additional question: What are the chances of the magician of keeping his physical brain and not having a new one ?

Quick analysis: One one hand, there is one magician alive, and 100 drowned magicians, so his chances are 1 out of 100.

On the other hand, each time he does the trick, he has 1/2 chances of staying alive, so his chances are $(1/2)^{100}=1/(2^{100})$ of staying alive.

What is the right response and why ?

You probably know the trick in the movie the prestige :

A magician has found an impressive magic trick : he goes into a machine, close the door, and then disappears and reappears in the other side of the room. But the machine is not perfect : instead of just teleporting him, it duplicates him. The magician stays where he is, and a copy is created at the other side of the room. Then, the magician in the machine falls discreetly in a water tank under the floor and is drowned. Edit: The probality of the new copy of magician being drowned is 1/2 (in other words, the new copy has 1/2 chances of being drowned, and 1/2 chances of poping in the room). Also, the water tank never fails and the chances that the magician droping in the tank dies are 1.

So the magician doesn't really like doing this trick, because "you never know where you are going to be, on the other side of the room or drowned".

Now, the paradox is the following : Imagine the magician does the trick 100 times. What are his chances of surviving ?

Edit, additional question: What are the chances of the magician of keeping his phisical brain and not having a new one ?

Quick analysis: One one hand, there is one magician alive, and 100 drowned magicians, so his chances are 1 out of 100.

On the other hand, each time he does the trick, he has 1/2 chances of staying alive, so his chances are (1/2)*100=1/(2^100) of staying alive.

What is the right response and why ?

You probably know the trick in the movie the prestige :

A magician has found an impressive magic trick : he goes into a machine, close the door, and then disappears and reappears in the other side of the room. But the machine is not perfect : instead of just teleporting him, it duplicates him. The magician stays where he is, and a copy is created at the other side of the room. Then, the magician in the machine falls discreetly in a water tank under the floor and is drowned. Edit: The probability of the new copy of the magician being drowned is 1/2 (in other words, the new copy has 1/2 chances of being drowned, and 1/2 chances of popping into the room). Also, the water tank never fails and the chances ar 1 that the magician dropping in the tank dies.

So the magician doesn't really like doing this trick, because "you never know where you are going to be, on the other side of the room or drowned".

Now, the paradox is the following : Imagine the magician does the trick 100 times. What are his chances of surviving ?

Edit, additional question: What are the chances of the magician of keeping his phisical brain and not having a new one ?

Quick analysis: One one hand, there is one magician alive, and 100 drowned magicians, so his chances are 1 out of 100.

On the other hand, each time he does the trick, he has 1/2 chances of staying alive, so his chances are $(1/2)^{100}=1/(2^{100})$ of staying alive.

What is the right response and why ?