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#1 2013-07-29 05:13:28

anna_gg
Member
Registered: 2012-01-10
Posts: 113

Pick Random Numbers

Get two random numbers between 0 and 1. Subtract the smaller from the bigger. What is the probability that the result is <0.3? Is it greater than the probability to be > or equal to 0.3?
For what number (instead of 0.3) the probability for both cases is the same?

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#2 2013-07-29 06:14:58

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,387

Re: Pick Random Numbers

Hi;

Is it greater than the probability to be > or equal to 0.3?

I am not understanding you here, the P(≥.3) = .49

Did you check your post about the towns?


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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#3 2013-08-01 04:22:58

anna_gg
Member
Registered: 2012-01-10
Posts: 113

Re: Pick Random Numbers

Correct.
So, to have equal probability for both cases, we have to substitute 0.3 with 1-sqrt(0.50) = 1-0.707 = 0.292

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#4 2013-08-01 06:13:04

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,387

Re: Pick Random Numbers

Hi;

Yes to get both equal to 1 / 2 we would need

Have you seen the answer given for,

http://www.mathisfunforum.com/viewtopic … 50#p279650


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

Online

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