A trait has two alleles and their frequencies are represented by P and Q if he equals 0.90 what is Q?

If the frequency of allele P is 0.90, then the frequency of allele Q can be calculated using the equation P + Q = 1. Therefore, if P = 0.90, then Q = 1 - 0.90, which equals 0.10. Thus, the frequency of allele Q is 0.10.