You could try with Jquery
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
</head>
<body>
<div id="divAllReports"></div>
<div id="divSum"></div>
<script src="jquery.js"></script>
<script type="text/javascript">
$(document).ready(
function() {
var sString = "";
sString += "<table>";
sString += "<tr>";
sString += "<td>ABC</td>";
sString += "<td>300</td>";
sString += "</tr>";
sString += "<tr>";
sString += "<td>PQR</td>";
sString += "<td>200.75</td>";
sString += "</tr>";
sString += "<tr>";
sString += "<td>xyz</td>";
sString += "<td>223</td>";
sString += "</tr>";
sString += "<tr>";
sString += "<td>xyz</td>";
sString += "<td></td>";
sString += "</tr>";
sString += "<tr>";
sString += "<td>xyz</td>";
sString += "<td>2</td>";
sString += "</tr>";
sString += "</table>";
document.getElementById("divAllReports").innerHTML = sString;
var sum = 0;
$('td:nth-child(2)').each(function () {
var value = Number($(this).html());
if (!isNaN(value)) sum += value;
});
$('#divSum').html(sum);
//
}
);
</script>
</body>
</html>