Can the amount of product at a given time be calculated with multiple reactants?

[djh101]

And by calculated I mean calculated in a fairly simple way. Single reactant problems have the integrated rate laws that relate time, final concentration, and initial concentration. However, I can't seem to find anything on calculating concentration at time t in a reaction with multiple reactants. The only way I can think of is integrating the inverse of the rate law to get a formula of time with respect to concentration. This solution worked fine for a single reactant rate law, but integrating a multiple reactant rate law a) seems a little over-complicated and b) is a little out of my reach, since I have yet to learn multivariable integration.

So anyway... is there a simple way to find out the concentrations of reactants/products over time in a multi-reactant reaction?

[DrDu]

In full generality this is difficult; think e.g. of oscillating reactions.