Aman has blood type ab and his wife has blood type b. what are the possible blood types for their child? blood types a and b blood type ab blood types a, b, and ab

The easiest way to solve this would be a punnet square. 

The man has AB Blood
The woman has BO Blood. 

The baby has 50% Chance of having type BO Blood
25% Chance of having AB Blood and
25% Chance of having AO blood.

So the child can have type B, AB, or A Blood!

Hope this helps!

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