// Numbas version: finer_feedback_settings
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Find a regression equation.
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\n\n\n\nStudent | \n$\\var{obj[0]}$ | \n$\\var{obj[1]}$ | \n$\\var{obj[2]}$ | \n$\\var{obj[3]}$ | \n$\\var{obj[4]}$ | \n$\\var{obj[5]}$ | \n$\\var{obj[6]}$ | \n$\\var{obj[7]}$ | \n$\\var{obj[8]}$ | \n$\\var{obj[9]}$ | \n
\n\nFirst Test $(X)$ | \n$\\var{r1[0]}$ | \n$\\var{r1[1]}$ | \n$\\var{r1[2]}$ | \n$\\var{r1[3]}$ | \n$\\var{r1[4]}$ | \n$\\var{r1[5]}$ | \n$\\var{r1[6]}$ | \n$\\var{r1[7]}$ | \n$\\var{r1[8]}$ | \n$\\var{r1[9]}$ | \n
\n\nLater Score $(Y)$ | \n$\\var{r2[0]}$ | \n$\\var{r2[1]}$ | \n$\\var{r2[2]}$ | \n$\\var{r2[3]}$ | \n$\\var{r2[4]}$ | \n$\\var{r2[5]}$ | \n$\\var{r2[6]}$ | \n$\\var{r2[7]}$ | \n$\\var{r2[8]}$ | \n$\\var{r2[9]}$ | \n
\n\n
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\ny = a + bx
\nFind $a$ and $b$ to 5 decimal places, then input them below to 3 decimal places.
\n$b=\\;$[[0]], $a=\\;$[[1]] (enter both to 3 decimal places).
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