First workout the different combinations between the two blood types. Then workout the different combinations for genders. Finally you would have each combination of genders for each blood type. To demonstrate:
Then for each of the blood types IAI,IBI,IAIB,II, there are the combinations of the genders i.e. .
From this you would infer there are 25% IAI,IBI,IAIB, II and for each 25% of these, there are 50% Dd and 50% dd.
In conclusion, the genotypes are:
12.5% ->>IAI Dd,IBI Dd,IAIB Dd, II Dd, IAI dd,IBI dd,IAIB dd, II dd.
The Phenotypes are:
A blood group male
B blood group male
AB blood group male
O blood group male
A blood group female
B blood group female
AB blood group female
O blood group female
~all with a percentage of 12.5%