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

anna_gg
Member
Registered: 2012-01-10
Posts: 231

### 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
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,133

### 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

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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

anna_gg
Member
Registered: 2012-01-10
Posts: 231

### 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
From: Bumpkinland
Registered: 2009-04-12
Posts: 107,133

### 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.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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