Polly suspects that a die is biased. The probability of the die landing on 6 is believed to be 0.4, and Polly thinks this probability has changed. The die is to be rolled 20 times, and X X\,X is the number of sixes obtained.
Write down the hypotheses Polly should use.
Using a 10% significance level, find the critical region for a two-tailed test, with a probability of at most 0.05 in each tail.
Find the actual significance level of a test based on this critical region.
Polly rolls the die 20 times and obtains 11 sixes. Comment on Polly's suspicion.
40 exam-style questions on WJEC A Level Maths 2.5 Statistical hypothesis testing, covering 2.5.1 Statistical hypothesis testing, 2.5.2 Statistical hypothesis testing, 2.5.3 Statistical hypothesis testing, 2.5.4 Statistical hypothesis testing, and 2.5 Statistical hypothesis testing. Each one has a worked solution and a mark scheme showing where the marks go.