1.6 Exponentials and logarithms

Easy Medium

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Question 16

The variables $x\,$ and $y\,$ are recorded and the results are shown in the table below


$x$	1	2	3	4	5	6	7	8	9	10
$y$	429	754	871	1119	2478	2653	3050	3279	5470	7439

The data is coded using the changes of variable $r = x$ and $s = \log_{10} y$

The product moment correlation coefficient for the coded data is 0.98 Comment on $r\,$ for this model and therefore justify the use of a model in the form $y = ab^x$ where $a\,$ and $b\,$ are constants

[3]

The regression line of $r\,$ on $s\,$ is found to be $s = 2.60 + 0.127 r$

Find the values of $a\,$ and $b$ , give your answers to 3 significant figures

[3]

1.6 Exponentials and logarithms Questions

A Level
Maths
1.6 Exponentials and logarithms

A Level
Maths WJEC
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