The values of x x\,x and y y\,y for six trials are
x123456y35881113\begin{array}{c|rrrrrr}x&1&2&3&4&5&6\\\hline y&3&5&8&8&11&13\end{array}xy13253848511613
Describe the correlation shown by the data.
A regression line for predicting y y\,y from x x\,x is y=1.943x+1.200y=1.943x+1.200y=1.943x+1.200. Estimate y y\,y when x=4.5x=4.5x=4.5.
Interpret the gradient in context if x x\,x is dose in mg and y y\,y is response score.
State one reason why using the line at x=20x=20x=20 would be unreliable.
105 exam-style questions on WJEC A Level Maths 2.2 Data presentation and interpretation, covering 2.2.1 Data presentation and interpretation, 2.2.2 Data presentation and interpretation, 2.2.3 Data presentation and interpretation, 2.2.4 Data presentation and interpretation, 2.2.5 Data presentation and interpretation, 2.2.6 Data presentation and interpretation, 2.2.7 Data presentation and interpretation, 2.2.8 Data presentation and interpretation, and 2.2 Data presentation and interpretation. Each one has a worked solution and a mark scheme showing where the marks go.