In a large group of employees, the probability that an employee has a company phone (PPP) is 0.45, the probability that they have a company laptop (LLL) is 0.60, and the probability they have both is 0.30.
Find the probability that a randomly chosen employee has a company phone or a company laptop, P(P∪L)P(P \cup L)P(P∪L).
Given that a randomly chosen employee has a company laptop, find the probability they also have a company phone, P(P∣L)P(P|L)P(P∣L).
Find the probability that a randomly chosen employee does not have a company phone, given that they do not have a company laptop, P(P′∣L′)P(P'|L')P(P′∣L′).
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.