A person's blood group is determined by whether or not it contains any of 3 substances AAA, B B\,B and CCC.
A doctor surveyed 300 patients' blood and produced the table below.
| Blood contains | No. of Patients |
|---|---|
| only CCC | 100 |
| A A\,A and C C\,C but not BBB | 100 |
| only AAA | 30 |
| B B\,B and C C\,C but not AAA | 25 |
| only BBB | 12 |
| AAA, B B\,B and CCC | 10 |
| A A\,A and B B\,B but not CCC | 3 |
Draw a Venn diagram to represent this information.
Find the probability that a randomly chosen patient's blood contains substance CCC.
Harry is one of the patients. Given that his blood contains substance AAA, find the probability that his blood contains all 3 substances.
Patients whose blood contains none of these substances are called universal blood donors. Find the probability that a randomly chosen patient is a universal blood donor.
11 exam-style questions on Edexcel A Level Old Maths Probability. Each one has a worked solution and a mark scheme showing where the marks go.