I am wanting to know how I can add the all of the selected prices in a
listbox? I need to add the selected prices altogether. The listbox
should have only the names of the products. The listbox should be like
below:

<select name="powertoolslist[]" size="5" multiple="multiple"
id="powertoolslist">
<option value="Product 1">Product 1 - $16 per year</option>
<option value="Product 2">Product 2 - $103 per year</option>
<option value="Product 3">Product 3 - $89 per year</option>
<option value="Product 4">Product 4 - $16 per year</option>
<option value="Product 5">Product 5 - $16 per year</option>
<option value="Product 6">Product 6 - $260 per year</option>
<option value="Product 7">Product 7 - $16 per year</option>
<option value="Product 8">Product 8 - $22.50 per year</option>
<option value="Product 9">Product 9 - $16 per year</option>
<option value="Product 10">Product 10 - $102 per year</option>
</select>

Can someone please help me with this? Thanks in advance.