

magicjohn2278 Special user Isle of Man UK 536 Posts 
OK, here is a six sided die. If you roll a ONE, you win and get back twice the amount of your bet. If not, I keep your bet.
"Ahh, “, you say, “But...my chances of winning are only one out of six." "True," I agree, "So I'll give you three tries to get a one." So consider this. Three tries, with each try having a 1/6 chance of winning. Your chances of winning are 3 x 1/6 = 3/6 or 5050. So it's a fair bet. Is it not? :die: 
TomasB Inner circle Sweden 1143 Posts 
And if you want to make it even fairer you can offer him money odds 1:2 if his number shows twice and odds 1:3 if they show three times. That's called Chuck a Luck and can be seen described at
http://www.themagiccafe.com/forums/searc......=4365108 /Tomas 
magicjohn2278 Special user Isle of Man UK 536 Posts 
Thanks for the link Tomas  I still can't see how it works (or doesn't!)
It certainly looks like a 50/50 bet  but obviously isn't. I think I confused myself in trying to calculate the actual odds of winning once out of the three rolls.... Three rolls, 18 possible outcomes, chance of a one showing is 3 out of the 18  which is equivalent to 1 out of 6.  The same as just rolling one die  I'm going wrong somewhere! 
TomasB Inner circle Sweden 1143 Posts 
John, rolling two dice gives 36 combinations and rolling three dice gives 6 times as many possible outcomes.
/Tomas 
magicjohn2278 Special user Isle of Man UK 536 Posts 
Quote:
On 20060322 13:28, TomasB wrote: Yes  but I'm only using one dice, and rolling it 3 times? 1 2 3 4 5 6 1 2 3 4 5 6 1 2 3 4 5 6 ..only 18 combinations? 
TomasB Inner circle Sweden 1143 Posts 
That doesn't matter. Imagine that you have three identical dice, roll one, place it aside, roll the next place it aside then roll the last one and place it aside. Using a single die three times is the same as using three dice once.
If the first roll is 1 and the second 1 you still have a total of six combinations with the last throw: 111 112 113 114 115 116 If the first throw is one and the second 2 you have six more as 121 122 123 124 125 126 so that's 12 combinations already and we haven't even gotten started in recording them all. There are a total of 6*6*6 outcomes with three throws. /Tomas 
LobowolfXXX Inner circle La Famiglia 1189 Posts 
Quote:
On 20060322 12:32, magicjohn2278 wrote: Well, it is not. To look at it another way, if you rolled the die SIX times, would the chances be 100%? Clearly not. The actual odds are 1[(5/6)(5/6)(5/6)]
"Torture doesn't work" lol
Guess they forgot to tell Bill Buckley. "...as we reason and love, we are able to hope. And hope enables us to resist those things that would enslave us." 
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