Prediction of progeny phenotypes and their relative frequencies (probabilities) from a cross between two heterozygotes becomes cumbersome as the number of heterozygous loci increases. This approach provides a practical accounting of all possibilites using the multiplication rule of probability.

Consider a cross between two individuals who are genotypically AaBbCc (where the three loci segregate independently). The table below shows the genotypic representation of the expected progeny phenotypes and their probabilities for each locus as well as the combination of all three loci. To obtain the phenotypic combinations and their probabilities, simply connect possibilities from each locus.

Notice that there are 8 possible phenotypic combinations.