I need to understand part b.

how did they get n(p)

in other words, how did they go from

p = F(n(p)) ......to n(p)

see the attachment!

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- Nov 6th 2009, 02:14 PMstatman101percentile help with CDF
I need to understand part b.

how did they get n(p)

in other words, how did they go from

p = F(n(p)) ......to n(p)

see the attachment! - Nov 6th 2009, 10:24 PMmatheagle
That's just the quadractic equation. Let x be the $\displaystyle p^{th}$ percentile

so p=F(x) or $\displaystyle p=2(x+{1\over x} -2)$

multiply by x and create a quad equation

$\displaystyle px=2(x^2+1 -2x)$

$\displaystyle x^2 -(2+{p\over 2})x+1=0$

NOW solve for x and discard the bad solution.