James runs a fish and chip shop. He records the average daily temperature, t∘Ct^{\circ}\text{C}t∘C, and the daily sales, £S\pounds S£S, for 12 days in the summer. The product moment correlation for these data is 0.61
Stating your hypotheses clearly and using a 5% significance level, test whether there is a positive correlation between daily sales and daily temperature.
James suggests that a linear regression model could be used to model the data.
State, giving a reason, whether or not the correlation coefficient is consistent with James's suggestion.
State, giving a reason, which variable would be the explanatory variable.
James calculated the linear regression equation as S=4932+ktS = 4932 + ktS=4932+kt
For every 1∘C1^{\circ}\text{C}1∘C increase in temperature sales increase by £128\pounds 128£128.
State the value of kkk.
340 exam-style questions on Edexcel A Level Maths Regression, Correlation and Hypothesis Testing, covering 1.1 Exponential Models, 1.2 Measuring Correlation, and 1.3 Hypothesis Testing for Zero Correlation. Each one has a worked solution and a mark scheme showing where the marks go.