web2.0calc
 

reinout-g

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Usernamereinout-g
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 #33
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+11
Here are the new probability puzzles!
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Easier one:

Ben the hiker wants to spend the night on top of a mountain. He hikes all day long towards the top and camps there overnight. The following day he is taking the same path down towards the bottom when he suddenly looks at his watch en notices that he is at the very same spot at the very same time of the day as the day before on his way up. 'What a coïncidence!' he exclaims!
Give an estimate of the probabilty that a hiker will be at exactly the same spot on the mountain at the same time of the day on his return trip as he was the previous day's hike up the mountain and explain why.

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Hard one :

You and your best friend have been arrested for several white collar crimes. (Or something else which is more classy than stealing a candy bar)
Your attorney has told you the police has only got enough evidence to put you and your friend behind bars for 3 years.
However, the both of you are given the option to confess. If both of you confess you will both serve 10 years,
if one of you confesses and the other does not, the one who did not confess will serve 20 years.
Obviously, if you both remain silent you will both serve 3 years.
You are not allowed to have any communication with your friend.
Suppose your main priority is to keep yourself out of jail, and your secondary priority is to keep your partner out of jail.
You have decided that you find it twice as important to keep yourself out of jail as you find it important to keep your partner out of jail.
(So for example, in your opinion him serving 10 years is equal to you serving 5).
You estimate the chance of your partner confessing p.
For which values of p will you choose to confess and for which values will you keep silent?

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Reinout-g

edit; I changed 'at what value of p' to 'for which values of p'
Apr 4, 2014
 #92
avatar+2353 
+6
Melody:

Hi everyone,
My last wrap was 3 days ago. I was not really intending to do one tonight. The regular posts were about to 'fall off the page' and I was seriouously considering leaving them there.
Anonymous4338 made me re-think. Thank you for your post on this thread. I am glad I made you happy. You have made me happy too.

Since my last wrap many great answers have been posted by Samgelinas, CPhill, Alan, Kitty<3, reinout-g, brabrams, guest, Rom and Anonymous4338. Thank you.

Samgelinas posted an addictive web game. Thanks for that. I have added the thread address to my collective 'games' thread.

I have written a post 'Information for new members' on the 'Become a member' thread. I have talked about a few things there, I can't actually remember what - You will have to take a look.
I have however explained how the private message system works. Unless you have any particular reason not to, it would be a good idea if you set an alert pop-up for new messages.
I have explained it all in the post. I sometimes want to contact members privately. This is the only way I can do it. Other people may also want to chat.
http://web2.0calc.com/questions/become-a-member-why-would-you-want-to
I think that is it for now.
Stay happy,
Melody.



Thanks Melody

I like the end of the day wrap up because it is usually there when I open the forum (which is usually around 2pm.)

It saves me the time of skimming through all posts which happened during the night (such as someone who gave an interesting theory or answer and also might remind me to eg. update the probability puzzles (which I totally forgot) or have another look at the calculator options, etc. In addition to that it gives me an idea of when you're about the log-out, which is usually when I refresh the forum a little more often.

Moreover when I first came to the forum it also motivated me to answer more questions since it kind off felt like an achievement to be in the wrap up.

Nevertheless I do understand that the forum has become less active and that it might be too much to post one every day.
Perhaps you could post one every once in a while just for the update.

Reinout
Apr 4, 2014