My LED calculator won't work

My LED calculator won't work

I'm trying to make a LED Calculator with jQuery, but it won't work.

Heres my index code:

<!DOCTYPE html>
<html>
<head>
<title>LED calculator</title>
<link rel="stylesheet" type="text/css" href="style.css">
<script src="jquery-1.11.2.js"></script>
<script type="text/javascript" src="script.js"></script>

</head>

<body>
<h1>LED Calculator</h1>

<input type="text" id="srcVol"> Source Voltage</input>
<br>
<input type="text" id="dioForVol"> Diode Forward Voltage</input>
<br>
<input type="text" id="dioForCur"> Diode Forward Current (mA)</input>

<br>
<button id="findR">Find R</button>

<div>
<p>Answer: </p>
</div>
</body>

</html>

Here's my jQuery code:
$(document).ready(function() {

var $srcVol = srcVol;
var $dioForVol = dioForVol;
var $dioForCur = dioForCur;

$("#findR").click(function() {
$srcVol = srcVol - dioForVol / dioForCur;
});

-----------------------

I wan't jQuery to print out the anwser on the screen (answer from the math syntax in the script), I've tried several different things for example: $("div").append(srcVol);

Is the way I made the math syntax wrong, or am i just stupid?

Please help!