So if you haven't been exposed to Geogebra, you should check it out. It's like the old TI graphing calculators but on steroids. You can run it as an application across the web through a browser (I've only tried Chrome). OR, you can download it as well. You can get a light version for your phone. It's pretty cool and not so much of a resource hog as things like Minitab or Excel. One of the powerful things about it, is you can assign "sliders" to terms of equations, pretty much at will. Then, you can grab the slider with your mouse and move it back and forth, or even animated it, and see in real time the effect of this on your graphs and following calculations. You can get to it here: https://www.geogebra.org/ I've built two models that you can open with this app (attached): Capability - Which plops a normal distribution down inside a set of limits. You can slider the mean, standard deviation, and the limits how you wish and it calculates Cp, CpU, CpL and Cpk in real time and shades the rejection regions. NonNormalCap - This one lets you specify the two different DOFs for an F-Distribution and it calculates the Cp, CpU, CpL, and Cpk of this F-Distribution by back calculating the reject regions areas. THEN it generates 100 random points from this F-Distribution and plots and calculates the data as if it were normal. You get to see the actual capability metrics against the ones you would get if you made the assumption it were normal when the underlying distribution is not. KEY POINT: The Geogebra default extension is ".ggb" but the forum will not allow files of this type to be uploaded. So I have renamed them to ".zip". When you download them, you need to change the extension back to ".ggb"