Badunit, Jerry, Barry, thank you.
I think it would help if I clarified what I am trying to do. A screenshot I think will make the matter obvious. I am trying to make a table that flows depending on the situation the user is in. One of the later formula-using data cells (C50) essentially depends on a piecewise-defined function (defined via formulae in C34-C36): basically, "If x ≥ y, then k = x*a. If x < y, then k = x*b," of course with these letters representing different numbers.
I wanted one cell to be a drop-down menu for x = ____ (C37, to select from C34-C36), then the later formula-cell (C50) to use that value (which I can do with the INDIRECT function), but I wanted that cell (C37) to read as the value of x, not as "C33", etc.
Below is the screenshot. k_Q depends on %dd(10), and %dd(10) is the piecewise function. The purple cells are Pop-up Menus, whose items are the values that will be encountered (e.g. from tabulated data, so the user has only to click, rather than type numbers manually), or else questions to say "yes" or "no" to (reminders, basically). The green cells contain formulas to automatically calculate a value based on measurements: The blank white cells are where the user will enter the measured value. Column C represents data for 6 MV, while column D represents data for 10 MV.
So you see why I want C37 and D37 to complete the statement, "%dd(10) = ____": It logically makes sense in the spreadsheet, and later cells depend on that value. I want it to be a Pop-up Menu, rather than direct data entry, because the procedure is repetitive, and there is less chance for error if one selects an entry rather than types raw numbers -- it's also easier for the user to click once than to type five keystrokes.
It makes the most sense to me if I could simply say "=C28" as the popup menu entry, so that it would refer to and display whatever is in cell C28. But as I said in the OP, typing '=C28' creates the string (text) '=C28', rather than what I want it to do.
Sorry for the exhaustive reply, but I felt it was appropriate to be explicit, given the detailed nature of the responses I've received. I entered the cell references after including the screenshot -- sorry if it was longwinded.
(By the way, Jerry, your responses are informative but difficult for me to understand. I am apparently not as experienced with Numbers as you are.)
