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#1 2006-07-09 12:22:20

babyangel1972
Member
Registered: 2005-12-12
Posts: 18

Help

Suppose the distribution of heights of a group of 400 children is normal, with a mean of 150 centimeters and a standard deviation of 12 centimeters.  About how many of these children are taller than 162 centimeters?

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#2 2006-07-13 01:36:59

George,Y
Member
Registered: 2006-03-12
Posts: 1,379

Re: Help

above 1 stdev above mean?
you should check out the equavalent probabilty distribution of a normal curve after 1.
∫N(0,1)dx from 1 to+∞
or 1-CDF(1) (1-Phi(1))
gross answer is 5%
Since probability within one sigma is 90%. And shorter than 138 share the same half with the taller than 162 ones.


X'(y-Xβ)=0

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