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### #1

Posted 10 November 2008 - 10:49 PM

How can this be done?

### #2

Posted 10 November 2008 - 10:52 PM

i have no idea... <_<

### #3

Posted 10 November 2008 - 11:04 PM

### #4

Posted 10 November 2008 - 11:22 PM

Past prime, actually.

### #5

Posted 10 November 2008 - 11:26 PM

And you do this blindfolded, also the coins are not in piles to start with ???I understood, the two piles do not need to have the same number of coins, just the same number of tails.

Spoiler for Solution

### #6

Posted 10 November 2008 - 11:31 PM

Is that difficult?And you do this blindfolded, also the coins are not in piles to start with ???

Past prime, actually.

### #7

Posted 10 November 2008 - 11:38 PM

Are the coins random or not??Is that difficult?

Spoiler for method

### #8

Posted 11 November 2008 - 12:08 AM

Lostinspace, it is random, but it doesn't matter.

### #9

Posted 12 November 2008 - 12:20 PM

mmm one small problem I don't have that many coins!

hehehe

### #10

Posted 12 November 2008 - 07:47 PM

You don't need actual coins to test that solution. Just imagine you set aside 30 coins. Then choose any number between 0 and 30. Say, you picked number 5. Now assume there are 5 tails among 30 coins set aside. Then there are 25 tails remaining in the other pile. There are also 25 heads in the 30-coin pile that you set aside. When you turn over every coin from the 30 set aside, you get 25 tails and 5 heads. Now recall, there are also 25 tails in the other pile.omg .... i can't believe that works... now I am going to have to go and try it myself!!!!

mmm one small problem I don't have that many coins!

hehehe

Repeat this exercise for every number of tails in the 30-coin pile between 0 and 30.

Past prime, actually.

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