Riddles

[Fantasygun]

You just take 10 random coins, and turn some of them over, never said to use all the coins

[GoLions]

Riddle #23

There are 100 coins scattered in a dark room. 90 have heads facing up and 10 are facing tails up. You cannot tell which coins are which. How do you sort the coins into two piles that contain the same number of tails up coins?

you flip them all on their edges.

Do you mean sideways? Because while I guess that would work, it isn't the correct answer.

You just take 10 random coins, and turn some of them over, never said to use all the coins

You need 2 piles

[Fantasygun]

The other pile is the other 90 coins in a pile, I'm probably way off

[GoLions]

The other pile is the other 90 coins in a pile, I'm probably way off

So you're saying, make 2 piles. One with 90 coins, one with 10 coins. Then flip over some of the coins in the pile of 10?

[Fantasygun]

Flip all of the coins in pile 10

[kilbluff1985]

Flip all of the coins in pile 10

there is no pile 10 just 10 of the coins tails are facing up you cant tell which ones

[kilbluff1985]

wait a minute if you cant tell which ones which then why the hell bother lol

hmm dark room? something to do with photography or something?

[Fantasygun]

I said take a group of random  10

[PowerBug]

feel the backs of the coins and put them into piles accordingly?

[CrowsFan]

Fantasy gun has basically got it, but I feel he hasn't explained it all that well. So I'll explain it for you guys.

So there are 100 coins, 90 heads and 10 tails.

Pick a random group of 10 coins and put them in a pile, call this Pile A. The other 90 are in another pile (pile B), so there are your two piles.

In Pile A you could have 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 coins showing tails. In Pile B it will be the complete reverse, so if there are 7 tails in pile A there will be 3 tails in pile B, or if there are 4 tails in pile A there will be 6 in pile B.

You get the 10 coins in pile A and flip them all over to face the other way. This means if there were 7 tails in pile A before there would now only be 3, which would match the same number in pile B.

Hope you all understand now :)

[GoLions]

Flip all of the coins in pile 10

That would be correct then.

For those who didn't follow, if you have 90 coins in one pile, and 10 coins in the other pile, in total, there will be 10 with tails facing up. Lets say that 7 were facing up in the pile of 90, that would mean 3 are facing tails up in the pile of 10. Now, if you flip over every coin in the pile of 10, there would now be 7 coins with tails facing up.

[GoLions]

CF just beat me to it, looks like we're even now  ;)

[CrowsFan]

CF just beat me to it, looks like we're even now  ;)

Haha we even used the same example of 7 tails :o

[GoLions]

CF just beat me to it, looks like we're even now  ;)

Haha we even used the same example of 7 tails :o

Hahaha yeah, guess great minds think alike?  :P

[Ziplock]

pretty sure I was right. This is why I dislike riddles :P