A botanist finds that for a specific species of hybrid orchid, the probability of an individual seed failing to germinate is 0.12.
In a tray containing 50 seeds, find the probability that at least 10 seeds fail to germinate.
A commercial nursery prepares a large batch of 250 seeds. The batch is classified as 'low yield' if more than 40 seeds fail to germinate.
Use a suitable approximation to calculate the probability that the batch is classified as low yield.
67 exam-style questions on OCR A Level Maths 2.4.4 Mean and variance of the binomial (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.