The probability that a specific variety of tomato seed fails to germinate is 0.06. A gardener plants several trays of these seeds.
Find the probability that
a tray containing 25 seeds has exactly 2 seeds that fail to germinate.
a larger batch of 100 seeds has more than 8 seeds that fail to germinate.
A commercial greenhouse plants a large shipment of 800 seeds.
Using a suitable approximation, find the probability that the greenhouse's shipment will contain less than 40 seeds that fail to germinate.
616 exam-style questions on Edexcel A Level Maths The Normal Distribution, covering 3.1 The Normal Distribution, 3.2 Finding Probabilities for Normal Distributions, 3.3 The Inverse Normal Distribution Function, 3.4 The Standard Normal Distribution, 3.5 Finding the mean and standard deviation, 3.6 Approximating a Binomial Distribution, and 3.7 Hypothesis Testing with the Normal Distribution. Each one has a worked solution and a mark scheme showing where the marks go.