How to solve ABO blood type questions using Venn Diagram
To solve this problem, we use a two-set Venn diagram where Circle A represents the A antigen and Circle B represents the B antigen. Step-by-Step Solution: 1. Fill in the Intersection (The overlap): Always start with the students who have both. n(A∩B)=7 (Type AB) 2. Calculate "Only A" (Type A): We know 42 students total have the A antigen, but this includes the 7 who also have B. n(Only A)=n(A)−n(A∩B) 42−7=35 3. Calculate "Only B" (Type B): We know 18 students total have the B antigen. n(Only B)=n(B)−n(A∩B) 18−7=11 4. Calculate the Union (Everyone with at least one antigen): Add the unique parts together: 35(Only A)+11(Only B)+7(Both)=53 5. Calculate "Neither" (Type O): Subtract the Union from the total population (100). 100−53=47 Final Answers: How many have only the A antigen? 35 students. How many have neither antigen (Type O)? 47 students. https://www.youtube.com/watch?v=YiVmwwk1RBM
To solve this problem, we use a two-set Venn diagram where Circle A represents the A antigen and Circle B represents the B antigen. Step-by-Step Solution: 1. Fill in the Intersection (The overlap): Always start with the students who have both. n(A∩B)=7 (Type AB) 2. Calculate "Only A" (Type A): We know 42 students total have the A antigen, but this includes the 7 who also have B. n(Only A)=n(A)−n(A∩B) 42−7=35 3. Calculate "Only B" (Type B): We know 18 students total have the B antigen. n(Only B)=n(B)−n(A∩B) 18−7=11 4. Calculate the Union (Everyone with at least one antigen): Add the unique parts together: 35(Only A)+11(Only B)+7(Both)=53 5. Calculate "Neither" (Type O): Subtract the Union from the total population (100). 100−53=47 Final Answers: How many have only the A antigen? 35 students. How many have neither antigen (Type O)? 47 students. https://www.youtube.com/watch?v=YiVmwwk1RBM