Arithmetic of Growth: Methods of Calculation,II

This calculational tutorial continues the presentation of an earlier article (Bartlett,1993 ). It starts with a news item that features one elderly person who has 67 grandchildren and 201 great grandchildren. This tutorial develops simple mathematical models to show how to calculate approximate average rates of growth of descendants using very simple assumptions plus the data from the news story. The model is then enlarged to describe the growth of populations and to see how the growth of populations is related to the growth of descendants and to fertility. The analysis is then generalized so it can be applied to other reproductive phenomena, such as the production of Ph.D.s. The goal is to illustrate the essential features of the simplest elements of the population growth process by introducing modeling that is within the reach of those who can use algebra.