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Old 2007 November 5th, 12:09 AM   #1 (permalink)
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Normal Distribution Q

So how do you solve this one? Thanks
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Old 2007 November 5th, 02:06 AM   #2 (permalink)
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Do we really have to measure the shape of the gauss curve or some crap like that?
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Old 2007 November 5th, 03:13 AM   #3 (permalink)
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Knock Out!
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Old 2007 November 5th, 09:11 AM   #4 (permalink)
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can you post it for the rest of us?

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Old 2007 November 5th, 09:44 AM   #5 (permalink)
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Originally Posted by DWarrior View Post
can you post it for the rest of us?

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He has already posted the question ! The attachment is the same image!
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Old 2007 November 5th, 09:49 AM   #6 (permalink)
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All I see is his first post:

Quote:
So how do you solve this one? Thanks
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and second post:

Quote:
Do we really have to measure the shape of the gauss curve or some crap like that?
I can't view the .bmp
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Old 2007 November 5th, 09:56 AM   #7 (permalink)
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Sorry DWarrior. But the image in his post was visible to me. So I thought it could be viewed by all. Anyway, I have posted it now.
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Old 2007 November 5th, 10:28 AM   #8 (permalink)
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Yeah, that is a tough one, can't really tell if that part is convex or concave without using the formula or having a stats chart.
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Old 2007 November 5th, 10:29 AM   #9 (permalink)
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Yeah, that is a tough one, can't really tell if that part is convex or concave without using the formula or having a stats chart.
True. I too need to revise my statistical concepts!
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Old 2007 November 5th, 12:34 PM   #10 (permalink)
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So I found the necessary property:
inflection points of a normal curve occur at +/- 1 SD away from the mean.

If you apply the 68/95/99.5 rule, we know the inflection point occurs at 34%, which is after the 30% mark, meaning the curve is bulging upwards at 30%.

450 is half-way between the two y-values, while 30% is half-way between the two x-values. The curvature is exaggerated for emphasis:

k<30, so B

Last edited by DWarrior : 2007 November 5th at 07:41 PM.
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