For anyone that has a copy of the book around, if you could follow me:
Figure 7.12 is equation 7.10 graphed (N as a function of P0)
Figure 7.13 is equation 7.15 graphed (M as a function of r)
But what equation represents figure 7.14? It is also M as a function of r. I don't understand what variable is replaced in equation 7.15 to get to this graph, and how you incorporate equation 7.16. I am an engineer graduate, and a few friends of mine sat around and tried to figure this out. Both figures 7.13 and 7.14 are different, but are graphing the same parameters.
Does it have to do with P0? P0 should represent the size of the fund at the end of the period worked such that it should last until the end of your life (or N+M=80). Should I replace P0 in equation 7.15 with N in equation 7.10? How does the constraint equation 7.16 get used?
Someone please help because this is driving me nuts.