Learn By Doing – Probability Rule Four
Recall the blood type example:
Here is some additional information
- A person with type A can donate blood to a person with type A or AB.
- A person with type B can donate blood to a person with type B or AB.
- A person with type AB can donate blood to a person with type AB only.
- A person with type O blood can donate to anyone.
Suppose that there are two patients who are each in need of a blood donation. Patient 1 has blood type A and patient 2 has blood type B. Consider randomly selecting a person (to be a blood donor) and define the following events:
- D1 — the randomly chosen person can be a donor for patient 1.
- D2 — the randomly chosen person can be a donor for patient 2.
This document is linked from Basic Probability Rules.