Marine biologists monitoring a coral reef find that the probability of a specific coral colony showing signs of thermal stress is 0.40. They survey a reef section containing 200 individual colonies.
Using a suitable approximation, estimate the probability that more than 75 colonies in the section show signs of thermal stress.
A researcher examines 3 separate sections of the reef, each containing 200 colonies.
Estimate the probability that at least 76 colonies show signs of thermal stress in each of the 3 sections.
292 exam-style questions on WJEC A Level Maths 4.2.2 Statistical distributions (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.