title: Calculation resulted in $NaN
body: <p>I think my issues is with parsing the "$" but I'm not sure how to go about resolving it. Here is the code:</p>
  
  <p><a href="https://jsfiddle.net/ottster/7oe9oy4a/" rel="nofollow noreferrer">https://jsfiddle.net/ottster/7oe9oy4a/</a></p>
  
  <p>could this "$" cause the issues with $NaN</p>
  
  <pre><code>$total = "$" + ($amount * $product); 
  </code></pre>