Put a dynamic value from js file to html

Put a dynamic value from js file to html

Well, I am working on some shopping cart script where I have a js that I
have included in my header as like
<script src="http://josscrowcroft.github.com/money.js/money.min.js"></script>
which is constantly updating the value of USD EUR etc.. and the function
is to call the script is
fx.convert(1, {from: 'EUR', to: 'USD'})
Now my question is I need the value of USD which will be converted from
EUR to show the customers both USD & EUR price which is in
as like
<div><h3>Product price 100 EUR or (USD value here) USD.</h3></div>
So how can I put the usd value there... ?