The scores on a standardised aptitude test are assumed to follow a normal distribution with a mean of 50 and a standard deviation of 8.
Using this model, find the probability that a randomly chosen candidate scores more than 65.
A researcher claims that the mean score of candidates from a specific region is higher than 50. A random sample of 64 candidates from this region has a mean score of 52. Test the researcher's claim at the 5% level of significance. You should state your hypotheses clearly.
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.