A method for selecting proportions of aggregate for incorporation into concrete comprises several steps. First, a maximum aggregate size for a specific application is determined. A sample of the maximum size aggregate is loose poured into a container. The percentage voids in that sample is then calculated. An amount of smaller sized aggregate equal to approximately the volume of percentage voids calculated earlier is added to the sample until a reduced volume of voids in the mixed sample is achieved. Finally, the amounts of aggregate determined to have the reduced volume of voids in the mixed sample are used in a concrete mixture.