PHP While Loop Summing

I am currently making a very standard ecommerce shopping cart, I have set it up so that the items display in the shopping cart looping onto a table from my database.

table class="large-16" style="margin-top: 20px;">
  <tr>
     <th>Action:</th>
     <th>Product:</th>
     <th>Price:</th>
     <th>Size:</th>
     <th>Color:</th>
     <th>Quantity:</th>
     <th>Price Total:</th>
   </tr>



  <?php while ($row = mysqli_fetch_array($result)) { ?>
    <tr>
      <td>
        <a href="delete-product-handler.php?id=<?php
          echo $row['product_id']; ?>" onclick="return confirm("Are you sure you want to remove this product from your shopping cart?")">
          <img src="img/delete.png" alt="delete button">Remove</a>
      </td>
      <td><?php echo $row['product_name']; ?></td>
      <td><?php echo $row['product_price']; ?></td>
      <td><?php echo $row['product_size']; ?></td>
      <td><?php echo $row['product_color']; ?></td>
      <td><?php echo $row['product_quantity']; ?></td>
      <td><?php $totalItemPrice[] = ($row['product_price'] * $row['product_quantity']);
            echo $totalItemPrice; ?></td>

    </tr>

As you can see it is set up to add up the Price of each item to the amount of the same item I wish to purchase.

How can I now add up the total of all the summed up prices to get an over all price of everything I am purchasing?