It isn't possible starting with what you posted. What are you trying to do? I'd like to help but this makes no sense at all.
Look at this and see if it gets you anywhere:
<pre>
<?php
$limitnum = "10";
$price = "19.2";
$data = array();
$total = 0;
for ($i = 0; $i < $limitnum; $i++)
{
$total += $price;
$data[$i] = $total;
}
print_r ($data);
?>
</pre>