This puzzle is similar to the first puzzle but with a few twists:
In this question:
- both my mom and I are blood type B.
- But this time I don't know my dad's blood type.
- My mom said her parents have the same blood type but is not the same as hers.
Given the above, how likely am I to be a pure blood? (Expressed as a percentage)
Explanation and clarification:
- Blood type in this question refers to the ABO blood type controlled by the A, B, O genes. Blood type A is either AA or AO, B is BB or BO, O is OO and AB is AB.
- Pure blood refers to a person having two identical blood type alleles, that is all people of blood type O (OO), some people of blood type A and B (AA, BB) but no one of blood type AB.
- Unless specified otherwise, a blood type A or blood type B person has a 50% chance of being a pure blood (AA, BB) and if a person's blood type is unknown, we can assume he's equally likely to be A, B, AB or O unless affected by his or her parents or children