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<script>
$(document).ready(function(){
$(document).ready(function () {
var sum = 0;
$("#product_table tr").each( function () {
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<table id=product_table>
<tr>
<td class="price">364.00</td>
<td class="quantity">3</td>
</tr>
<tr>
<td class="price">900.00</td>
<td class="quantity">2</td>
</tr>
<tr>
<td class="price">450.00</td>
<td class="quantity">1</td>
</tr></table>