A botanical research company specializes in a hybrid variety of orchid seeds. It is found that the probability of a single seed producing a 'Gold-veined' flower is 0.2.
Determine the probability that in a randomly selected packet of 25 seeds, exactly 3 seeds produce Gold-veined flowers.
A wholesaler purchases 5 of these 25-seed packets. Calculate the probability that exactly two of these packets contain at least 8 seeds that produce Gold-veined flowers.
A large experimental plot is planted with n n\,n seeds of this hybrid orchid. Using a normal approximation, it is found that the probability that at least 95 seeds produce Gold-veined flowers is 0.0401. Find the value of nnn.
390 exam-style questions on OCR A Level Maths 2.4 Statistical Distributions, covering 2.4.1 Discrete probability distributions, 2.4.2 Binomial distribution as a model, 2.4.3 Calculating binomial probabilities, 2.4.4 Mean and variance of the binomial (A-level only), 2.4.5 Normal distribution as a model (A-level only), 2.4.6 Probabilities using the normal distribution (A-level only), 2.4.7 Links to histograms, mean and standard deviation (A-level only), and 2.4.8 Selecting an appropriate distribution (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.