The age (a a\,a years) and height (h h\,h metres) of 10 oak trees were measured.
The product moment correlation coefficient for this data set is r=0.750r = 0.750r=0.750.
Stating your hypotheses clearly test, at the 1% significance level, whether there is a positive correlation between tree age and height.
51 exam-style questions on Edexcel A Level Maths 1.3 Hypothesis Testing for Zero Correlation. Each one has a worked solution and a mark scheme showing where the marks go.