The proportion of visitors to a webpage who click on a link is 0.15. Angela believes that increasing the font size of the link will increase this proportion.
After the font size is increased, a random sample of 90 visitors is taken, and 20 of them click on the link.
Stating your hypotheses clearly, test Angela's belief at the 5% significance level.
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.