[ExI] logic puzzle

[deimtee]

On 1/31/19 4:03 AM, spike at rainier66.com wrote:
> -----Original Message-----
> From: extropy-chat <extropy-chat-bounces at lists.extropy.org> On Behalf Of
> BillK
> Sent: Wednesday, January 30, 2019 8:38 AM
> To: ExI chat list <extropy-chat at lists.extropy.org>
> Subject: Re: [ExI] logic puzzle
>
> On Wed, 30 Jan 2019 at 14:57, spike wrote:
> <snip>
>> (OK, I follow them up to this point.)
>>
>>> ... Since ABAAX is dependent on the outcome of 4 games instead of 5, it is twice as likely to occur and can be treated as two possibilities.
>> (!)
>> (Indeed?)
>> (If so, I need to understand the heck outta this concept, otherwise I will miss every one of these.)
>
>> ...There is a solutions pdf that explains the probabilities in more detail.
> Page down to Problem 18.
>
> <http://hub.wastudentmath.org/TestFiles/Amc10/Amc10_2005_Individual_0.10_A_A
> .pdf>
>
>
> BillK
>
>
> OK cool, thanks BillK that does make sense I suppose.
>
> Sheesh probability is a crazy thing.
>
> spike
>
> _

Just to throw a spanner in the works,  given the Bananas won the second 
match, if they won the first match, the only way for the Apples to win 
the series would be to win matches 3, 4 and 5.  The probability of this 
is .5*.5*.5  or 1/8.  The odds that they won the first match is 
therefore 7/8.

-David.