A botanist claims that 35% of a rare wildflower species in a particular region have white petals. A local conservationist believes that the actual proportion of white-petalled flowers is significantly greater than this. In a random survey of 120 flowers of this species, 55 are found to have white petals.
Use a suitable approximation to test, at the 1% level of significance, whether there is evidence to support the conservationist's belief. State your hypotheses clearly.
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.