1. A computer readable medium having instructions stored thereon that, when executed by a processor, causes the processor to determine product pricing for a product category, the instructions comprising: receiving a non-linear problem for the product category, wherein the non-linear problem comprises a demand model; for a plurality of pair of products in the product category, determining coefficients for a change in demand of a first product when a price of a second product is changed; generating an approximate Mixed Integer Linear Programming (MILP) problem comprising a change of demand based on a sum of the determined coefficients; and solving the MILP problem to obtain a MILP solution, wherein the MILP solution provides the product pricing.