A wildlife conservation park employs 200 staff members divided into three departments: Enclosures, Veterinary, and Education. Each staff member is on either a Full-time or Part-time contract.
The distribution of staff members is shown in the table below:
| Contract Type | Enclosures | Veterinary | Education |
|---|---|---|---|
| Full-time | 45 | 15 | 20 |
| Part-time | 55 | 25 | 40 |
A staff member is selected at random. Find the probability that: (i) the staff member is on a Full-time contract. (ii) the staff member works in the Enclosures department.
Given that a randomly chosen staff member is on a Part-time contract, find the probability that this staff member does not work in the Veterinary department.
The park director wants to select three different staff members at random to form a focus group. Calculate the probability that all three staff members chosen work in the Enclosures department.
200 exam-style questions on OCR (MEI) A Level Maths 2.3 Probability, covering 2.3.1 Calculate the probability of an event, 2.3.2 Complementary events, 2.3.3 Expected frequency of an event, 2.3.4 Diagrams to calculate probabilities, 2.3.5 Mutually exclusive and independent events, 2.3.6 Add probabilities for mutually exclusive events, 2.3.7 Multiply probabilities for independent events, 2.3.8 Mutually exclusive and independent events (notation) (A-level only), 2.3.9 Venn diagrams for probabilities (A-level only), 2.3.10 Conditional probabilities (A-level only), and 2.3.11 Independence via conditional probability (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.