This paper extends the authors' method of calculating average physical properties of ideal nonlinear, stepwise polymerizations to systems with nonequally reactive functional groups. Two special cases are considered in detail: Af+A2+B2, where the two B units comprising a B2 monomer react at different rates; and Af+A2+B2, where one or two A units on the Af monomer may react at different (slower) rates than the remaining A's. Weight average molecular weight, the gel point, weight fraction solubles, and cross-link density are derived. These properties are calculated for several systems with unequal, first-order reaction rates and are compared to the corresponding properties for the analogous ideal systems. It is indicated how to extend this approach to other systems with unequal reactivity.