A geneticist postulates that in the progeny of a certain dihybrid cross, the four phenotypes should be present in the ratio 9:3:3:1. So if p1, p2, p3, and p4 are the probabilities associated with these four phenotypes, the issue is whether there is empirical evidence indicating that H0: p1 = 9/16, p2 = 3/16, p3 = 3/16, p4 = 1/16 should be rejected.
The observed frequencies corresponding to these four phenotypes, among 800 members of the progeny generation, are 439, 168, 133, and 60. Test H0 using α = .05.