To illustrate various mathematical methods which may be used to solve
problems of engineering, mathematical physics, and mathematical biolog
y, Volterra's model for population growth of a species in a closed sys
tem is solved using several methods familiar to junior-or senior-level
students in applied mathematics. Volterra's model is a first-order in
tegro-ordinary differential equation where the integral term represent
s the effect of toxin accumulation on the species. The solution method
s used are (i) numerical methods for solving a first-order initial val
ue problem supplemented with numerical integration, (ii) numerical met
hods for solving a coupled system of two first-order initial value pro
blems, and (iii) phase-plane analysis. A singular perturbation solutio
n previously presented is also outlined. While conclusions drawn using
the four methods are correlated, the student may analyze and solve th
e problem using any of the methods independently of the others.