The picture below shows a simple example of the problem I'm facing. I'd like to maximize a cell that is the sum of other cells that are not linear. In the spreadsheet, I have Z scores for categories I and II (I hardcoded in a mean of 30 and stdev of 15 for category I and 40 and 10 for category II), but do not want to maximize those z-score sums. I want to maximize the sum of their normdist values in G13. Clearly, solver won't find a linear solution. I have heard there was a way to get around this by doing piecewise-linear approximation.
//i.imgur.com/pwZVBSR.png