The daily rainfall in a certain region during the monsoon season is modeled by a normal distribution with a mean of 22 mm and a standard deviation of 6.8 mm. A researcher believes that recent climate shifts have caused the mean daily rainfall to increase. A random sample of 40 days during the current monsoon season is taken, and the mean daily rainfall is found to be 24.5 mm. Carry out a hypothesis test at the 5% significance level to investigate the researcher's claim.
162 exam-style questions on AQA A Level Maths 2.5 O: Statistical hypothesis testing, covering 2.5.1 Language of hypothesis testing, 2.5.2 Hypothesis test for a binomial proportion, and 2.5.3 Hypothesis test for a Normal mean (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.