You need maths for genetics. Elementary mathematics is required for Blueprint of Life and the option Genetics: the Code Broken?
Students are asked to construct pedigrees and punnet squares, and to do so they must utilise mathematical reasoning and have a basic grasp of percentages and ratios.
When you study Biology in university, there is definitely maths in it. Genetics gets a lot more complicated, esp. if you do a Bachelor of Genetics at ANU or a Bachelor of Science (Molecular Biology and Genetics) at USyd. It's quite ignorant of you to assume that Biology requires zero mathematics. There is a tiny amount of maths required for HSC Biology and when you hit university and major in Bio mathematics is a requirement of the degree.