The variables x x\,x and y y\,y are recorded and the results are shown in the table below
| xxx | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| yyy | 429 | 754 | 871 | 1119 | 2478 | 2653 | 3050 | 3279 | 5470 | 7439 |
The data is coded using the changes of variable r=xr = xr=x and s=log10ys = \log_{10} ys=log10y
The product moment correlation coefficient for the coded data is 0.98 Comment on r r\,r for this model and therefore justify the use of a model in the form y=abxy = ab^xy=abx where a a\,a and b b\,b are constants
The regression line of r r\,r on s s\,s is found to be s=2.60+0.127rs = 2.60 + 0.127rs=2.60+0.127r
Find the values of a a\,a and bbb, give your answers to 3 significant figures
278 exam-style questions on CCEA A Level Maths 2.5 Data presentation and interpretation, covering 2.5.1 Data presentation and interpretation, 2.5.2 Data presentation and interpretation, 2.5.3 Data presentation and interpretation, 2.5.4 Data presentation and interpretation, 2.5.5 Data presentation and interpretation, 2.5.6 Data presentation and interpretation, 2.5.7 Data presentation and interpretation, 2.5.8 Data presentation and interpretation, 2.5.9 Data presentation and interpretation, and 2.5 Data presentation and interpretation. Each one has a worked solution and a mark scheme showing where the marks go.