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# Darts at Morty's

16 replies to this topic

### #11 EventHorizon

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Posted 24 July 2012 - 01:12 AM

Spoiler for I looked at this puzzle last night...

Since then I've decided that....
Spoiler for Alex is a MACHINE!

Though perhaps I'm reading too much into it...
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### #12 ujjagrawal

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Posted 24 July 2012 - 07:11 AM

When Davey and Ian playing together:

Combined probability of hitting a bull's eye will be -

90% + 10% x 80% = 98% (If Davey fails to hit, when going first)
or
80% + 20% x 90% = 98% (If Ian fails to hit, when going first)

Clearly, more than 97% probability by Alex, so Alex definitely made a BAD bet.
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### #13 mrzinks

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Posted 24 July 2012 - 11:46 AM

Spoiler for Hmmm.....

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### #14 Rockmond

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Posted 24 July 2012 - 07:36 PM

Curr3nt did a lot of figuring to come up with the same conclusion I got by multiplying .1 by .2 and comparing it to .03. On 100 throws Alex loses a net 1 time.
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### #15 Rockmond

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Posted 24 July 2012 - 07:49 PM

When Davey and Ian playing together:

Combined probability of hitting a bull's eye will be -

90% + 10% x 80% = 98% (If Davey fails to hit, when going first)
or
80% + 20% x 90% = 98% (If Ian fails to hit, when going first)

Clearly, more than 97% probability by Alex, so Alex definitely made a BAD bet.

Easier to just calculate odds of neither Davey or Ian hitting bullseye: .1 * .2 = .02 or 2%
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### #16 jim

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Posted 25 July 2012 - 10:10 PM

Suppose they each throw 100 times with 97 bullseyes for Alex while Davey gets 90 and Ian gets 80. What would the team of Davey and Ian score? Suppose Davey throws first and misses 10 times. Ian lets the pressure get to him and misses every time Davye does.lus 10 additional times. In this case the team scores 90. On the other hand, if Davey is good under pressure and makes all 10 of those throws while missing on 20 other occassions, then the team scores 100. If the correlation coefficent for Davey and Ian is zero, then the team scores 98 and they win. With a negative correlation they do even better, but with a large enoiugh positive correlation the bet will be a good onwe for Alex.
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### #17 TheChad08

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Posted 26 July 2012 - 05:35 PM

Suppose they each throw 100 times with 97 bullseyes for Alex while Davey gets 90 and Ian gets 80. What would the team of Davey and Ian score? Suppose Davey throws first and misses 10 times. Ian lets the pressure get to him and misses every time Davye does.lus 10 additional times. In this case the team scores 90. On the other hand, if Davey is good under pressure and makes all 10 of those throws while missing on 20 other occassions, then the team scores 100. If the correlation coefficent for Davey and Ian is zero, then the team scores 98 and they win. With a negative correlation they do even better, but with a large enoiugh positive correlation the bet will be a good onwe for Alex.

You're using factors that aren't given to us and over examining the question.

What is 1 + 1?
Answer is 2
But what if I add to the question (like you) and turn it into 1 half + 1 half.
Then the answer would be 1.
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