>>>>>>Hi,
>>>>>>
>>>>>>>Next toss it's not 1:4 you'll get heads, then for a third 1:16 (1:8 or whatever) - it's still 1:2. By the end of 64 tosses, by that logic, like the old grains of sand on a chessboard conundrum, the chances of getting heads would be practically infinity:1.
>>>>>>
>>>>>>We're talking about the difference between getting heads on any one throw and getting heads *every time* in a series of throws. Your logic would dictate that there's a 50/50 chance of throwing heads an infinite number of times in succession<g>
>>>>>
>>>>>No, the argument was about the chances of winning the lottery twice, not "*every time* in a series of " entries.
>>>>>
>>>>>The chances of getting heads FIVE TIMES, in, say, 10 throws is 1:2
>>>>>
>>>>>The chances of getting heads TWICE in 10 throws are BETTER than 1:2 (I'd take any bet on that!)
>>>>
>>>>If you mean *at least* twice you'd be right. But your logic is still wrong.
>>>
>>>Yeah, agreed. I wouldn't be so keen to bet that I'll defo get just 2 heads.
>>>
>>>>
>>>>How about a deck of cards. The chances of the top card being, say, a king is 13-1. The chances of the second card being a king is slightly better . But the chances of there being two kings on top is 221-1 (13 * 17).
>>>
>>>But if you have several decks of cards, as you draw from each, once, your chance of getting a king, in each deck, is 13-1 each deck.
>>
>>Agreed, 13-1 each time. So assume two decks. The chances of getting a king on top of both decks (ie winning both) is NOT 13-1. Anytime you want to take those odds on being successfull I'm your man! <g>
>
>So the chances are (13 * 13): 1 ?
>


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Give yourself a pat on the back and take the rest of the day off ;-)