In a regional market survey, it is observed that approximately 35% of visitors to a specific artisanal craft market make a purchase from a pottery stall.
Determine the probability that in a randomly selected group of 75 visitors, at least 32 of them make a purchase from the pottery stall.
Find the probability that in a randomly selected group of 12 visitors, exactly 5 of them make a purchase from the pottery stall.
Using a suitable approximation, find the probability that in a randomly selected season where there are 1200 visitors to the market, there are at least 450 who make a purchase from the pottery stall.
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.