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Topic: Help with probability&stat problem
Replies: 47   Last Post: Jun 16, 2007 4:32 AM

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 tutorny Posts: 39 Registered: 1/28/06
Re: Help with probability&stat problem
Posted: Jun 11, 2007 1:34 PM

> Do you really think there is a 97% chance that
> there will be a 30% drop out rate? Suppose I asked
> you the probability that 100 of the students would
> drop out. How would you calculate that? Do you think
> that is a higher probability than only 30 students
> dropping out?

I am not entirely sure that I follow. 30 students out of 110 is 27%.
So if a 20% rate is to be expected, isn't it feasible that a 27% rate
is 96% likely?

If I made the mistake there, it would be in making p = 0.20. So, I
think what you are saying is that p should be = 0.80. But doing the
calculations that way results in a nonsensical answer..

If p =0.80 :
mean = 88, s.d. = 4.1952
and for x = 29.5, z = -13.944 which doesn't make any sense.

So where did I go wrong? Or am I not understanding your comment
correctly?

Date Subject Author
6/11/07 tutorny
6/11/07 briggs@encompasserve.org
6/11/07 tutorny
6/11/07 Randy Poe
6/11/07 tutorny
6/11/07 Bruce Weaver
6/11/07 tutorny
6/11/07 Bruce Weaver
6/11/07 C6L1V@shaw.ca
6/11/07 Randy Poe
6/11/07 tutorny
6/11/07 Nick
6/11/07 Jack Tomsky
6/11/07 Luis A. Afonso
6/11/07 Jack Tomsky
6/11/07 Luis A. Afonso
6/11/07 Jack Tomsky
6/12/07 Luis A. Afonso
6/12/07 Jack Tomsky
6/12/07 Luis A. Afonso
6/12/07 Jack Tomsky
6/12/07 Luis A. Afonso
6/13/07 Jack Tomsky
6/13/07 Luis A. Afonso
6/13/07 Anon.
6/13/07 Jack Tomsky
6/13/07 Jack Tomsky
6/13/07 Luis A. Afonso
6/13/07 Jack Tomsky
6/13/07 Anon.
6/13/07 Luis A. Afonso
6/13/07 Jack Tomsky
6/13/07 Jack Tomsky
6/13/07 Anon.
6/13/07 Luis A. Afonso
6/13/07 Jack Tomsky
6/13/07 Luis A. Afonso
6/13/07 Jack Tomsky
6/14/07 Luis A. Afonso
6/14/07 Luis A. Afonso
6/14/07 Jack Tomsky
6/14/07 Luis A. Afonso
6/15/07 Luis A. Afonso
6/15/07 Jack Tomsky
6/15/07 Luis A. Afonso
6/15/07 Jack Tomsky
6/15/07 Luis A. Afonso
6/16/07 Luis A. Afonso