HTML/PHP/Javascript problem.

[gsf600y]

I've been scratching my head on this one, but my Javascript skills are rubbish, so I'm struggling on working out how to do this......
I've got a HTML form. A basic version is as follows:

<form>
 <select name=select1>
  <option selected>Please Choose</option>
  <option value=option1>Option 1 £100.00</option>
  <option value=option2>Option 2 £200.00</option>
  <option value=option3>Option 3 £300.00</option>
 </select>
 <select name=select2>
  <option selected>Please Choose</option>
  <option value=option1>Option 1 £100.00</option>
  <option value=option2>Option 2 £200.00</option>
  <option value=option3>Option 3 £300.00</option>
 </select>
</form>

Note, the actual form select options are populated using PHP code pulling data from a database. The data pulled is the "value=xxxxxx" and the actual "Option x £xxx.xx".

Basically, what I want to do is total up the sum of the options selected.
Example:
If someone selects Option 1 for select1, and Option 3 for select2, the total would show £400.00

I want the display to update dynamically, before the form is submitted, so I was thinking JavaScript is the answer.

I've trawled lots of websites and tried a couple of things, but I really am utterly stuck on how to do this, although I'm sure it's perfectly possible.

Someone help me!!

 

[gsf600y]

That's superb!
Is there a way though to pull the number (eg.300) from the text in between the <option> </option tags?
I'm currently using value= to pass an item code over.
eg

<option value=000142 name=item1>Item 1, worth £152.44p</item>
<option value=000143 name=item2>Item 2, worth £474.83p</item>

Sorry to be fussy....I feel very ungrateful! Appreciate your help a lot

 

[gsf600y]

jdickerson - thanks mate. What I was meaning was to grab the value using Javascript, and use it for the total sum.

Geforce - okay, I've made that change so that "value" now looks like:

<option value=001_3.5>Item 001 worth £3.5m</option>
<option value=002_8.2>Item 002 worth £8.2m</option>

I'll need to alter the PHP that then processes those values to remove the _3.5 bit, but I can do that.

So, is it possible using the JavaScript to grab the _3.5 part, and use that number for doing the sums?