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#5 Re: Help Me ! » Probability of meeting » Today 03:16:22


Your formula for the probability checks out.

This is what I am getting for the expectation


where the horizontal axis is the waiting time and the vertical is the expected time to wait. But it was done while I am half asleep and needs some checking.

The formula that produces this graph is the piecewise function:

Surprisingly this says that the expected waiting time is 10 after t >= 30.

#6 Re: Help Me ! » Probability of meeting » Yesterday 22:38:31

If no one else can get it I will work on it tomorrow, I am exhausted from taking a long biking trip and having to return in the night through the forest. Much stress, much fear and much adrenalin seems to have drained the energy right out of me.

One thing still puzzles me, since I was interpreting the overlaps wrong I was getting the expectation wrong. How was I getting the probability right?

#7 Re: Help Me ! » The Earth and The String » Yesterday 22:25:19

You know I am one of those crazy ole guys who does not want to do math the same way Euclid did it. For some nutty reason I want to use electricity to assist me in mathematics. Yea, I am a screwball. Why not write up how you did it in Geogebra in computer math?

#8 Re: Help Me ! » The Earth and The String » Yesterday 21:42:09

Nope, you know how much I hate geometry questions. To me, geometry is done with the Geebra or M.

#13 Re: Help Me ! » Probability of meeting » Yesterday 16:06:24


So, in order to graph it all one needs is a general formula for the expectation and the probability. t will be the independent variable.

#14 Re: Help Me ! » The Earth and The String » Yesterday 16:04:09


I think I see what your problem is... I do not know if your answer is wrong. You are misinterpreting what I was saying in that earlier post.

I was saying that

and that

I never meant to imply that this formula is the solution to that problem. It may be or it may not. Having not worked on this problem at all I have no idea what the right answer is.

#15 Re: Help Me ! » The Earth and The String » Yesterday 13:59:18


I do not think FindRoot is making a mistake.

#16 Re: Help Me ! » Help with snakey word problem » Yesterday 08:03:45


Since I never played snakes and ladders, we had a different variant of it back when I was a kid, can you phrase your question a bit more mathematically? What do you want to know about those dice throws?

#17 Re: Help Me ! » Quantifying Exponential Population Growth of Ravens » Yesterday 06:26:18

Of these 7, due to juvenile bird mortality rates 3 come of age at 3 years old and go on to produce their own off spring for their breeding life.

Is that mortality rate yearly?

#18 Re: Help Me ! » Help with snakey word problem » Yesterday 06:21:42


Which one is the foot of the ladder? Nothing is mentioned about it until the end question.

#20 Re: Help Me ! » The Earth and The String » Yesterday 06:12:12

What is the name of the site?

#25 Re: Help Me ! » Probability of meeting » 2016-09-25 16:05:12

That would mean you could only have two parameters?! The waiting time for both would have to be the same?

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