Welcome to the boards... sometimes the answer comes quicker than other times, but all in all, we got a good core of regs who will hook you up pretty quickly, and since they are all over the world, you'll usually get answers quickly any time of day.
OK, let's go back to your original post...
<?php
foreach ($_POST as $key=>$value) {
if ($key!="Sumbit") {
$value=htmlentities (stripslashes (strip_tags ($value)));
echo "\t<input type=\"hidden\" name=\"$key\" value=\"$value\">\n";}}
?>
You would know that the 2 values are two of these hidden fields, so on page five, you could do the math from say:
$POST['valuepage3'] and $POST['valuepage4']
So, on page five, you could do...
$total = round(($_POST['valuepage3'] + $_POST['valuepage4']), 2);
echo "$".$total." USD";
What you want to make sure of is that your values are passed as integers and not as strings with the dollar sign and all... So, just pass 10.25 and 15.30. Then when you add the numbers on page five, you would just echo the dollar sign like above.
Is this getting you closer, or ar we still not quite on the same page here?