how to get the x-value which gives me 50% of area under a curve
I have some continuous data and I fit a curve using "Fit Model" and used attributes "Knotted Spline Effect" and 50 knots. Then I save the prediction formula to the table. What I want to do next is to find the fragment size (x-value) which gives me 5%, 10%, 25%, 50%, 75%, 90% and 95% of area. I have 10 samples and so I have 10 very complicated equations.How do I get the fragment size (x-value) with...