A farmer plants three varieties of tomato seeds: Variety A, Variety B, and Variety C. Variety A makes up 35% of the crop, Variety B makes up 45%, and Variety C makes up 20%.
The probability that a seed fails to germinate is:
Draw a tree diagram to show this information.
A seed is selected at random. Find the probability it fails to germinate.
Given that a seed failed to germinate, find the probability it was Variety B.
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.