When a person pledges to donate the value (the demei, דמת ) of a particular person to the temple (i.e. “I pledge to donate the value of that person over there) then he is required to give an amount of money equal to what that person would be worth as a slave. If person pledges to donate the eirech (ערך) of a person then it is assumed that he is referring to a special evaluation based on the calculations in Vayikra (27: 1-7). This Parsha outlines the value of people as follows:
Rashi says that as a woman ages she retains more of her value than a man does. (Rashi on Vayikra 27:7)
A. What is the rate of change for a man when he turns 60?
The value goes from 50 to 15 = change 35
35 / 50 = rate of change 70%
B. What is the rate of change for a woman when she turns 60?
20/30 = rate of change 66 2/3 %
C. What is the difference in the rate of change between a man and a woman when they reach 60?