The ratio of donors blood group ‘A’ to the average of the donors group ‘O’, ‘B’ and ‘AB’ is:

Answer: Option D

Average of O, B, AB blood group
$$\begin{array}{rl}& =\frac{100.8°+129.6°+57.6°}{3}\\ & =\frac{288°}{3}\\ & =96°\\ & \therefore \text{Required ratio}\\ & =72°:96°\\ & =3:4\end{array}$$