title: Javascript numbers concatenate instead of adding but typeof is number not string
body: <p>I am new to javaScript. I am building a calculator <a href="http://jsfiddle.net/RqzPk/7/" rel="noreferrer">here</a></p>
  
  <p>I have stored the input values in variables so that I can eventually manipulate the results to perform calculations based on input. For now I just want all of the values to add together.</p>
  
  <p>However, rather than adding, they are concatenating. I used parseInt to prevent javascript from viewing the numbers as strings, and typeOf reveals that they are numbers.</p>
  
  <p>Here is my javascript:</p>
  
  <pre><code>$(document).ready(function() {
  
  var theTerm = $("#theTerm").val();
  var theRate = $("#theRate").val();
  var thePrice = $("#thePrice").val();
  var theTax = $("#theTax").val();
  var theDown = $("#theDown").val();
  var theTrade = $("#theTrade").val();
  var theResult = parseInt(theTerm + theRate + thePrice + theTax + theDown + theTrade, 10);
  
  $("#calculate").click(function(){
      alert(theResult);
      alert(typeof(theResult));
  });
  
  }); 
  </code></pre>
  
  <p>and the HTML:</p>
  
  <pre><code>&lt;div id="calculator"&gt;
  &lt;span id="calculatorHeader"&gt;Monthly Payment Calculator&lt;/span&gt;
  &lt;table style="margin:0 auto;"&gt;
      &lt;tr&gt;
      &lt;td style="width:40px;"&gt;Term
          &lt;input id="theTerm" size="5" value="7" name="term" style="width:35px" /&gt;
      &lt;/td&gt;
      &lt;td style="width:40px;"&gt;Rate(%)
          &lt;input id="theRate" size="5" value="7" name="apr" style="width:35px" /&gt;
      &lt;/td&gt;
      &lt;td style="width:55px;"&gt;Price($)
          &lt;input id="thePrice" size="6" maxlength="7" name="price" style="width:50px" value="7" /&gt;
      &lt;/td&gt;
      &lt;td style="width:40px;"&gt;Tax(%)
          &lt;input id="theTax" size="4" maxlength="7" name="tax" style="width:35px" value="7" /&gt;
      &lt;/td&gt;
      &lt;td style="width:40px;"&gt;Down($)
          &lt;input id="theDown" size="5" maxlength="7" name="downPmt" style="width:35px" value="7" /&gt;
      &lt;/td&gt;
      &lt;td style="width:40px;"&gt;Trade($)
          &lt;input id="theTrade" size="5" maxlength="7" name="trade" style="width:35px" value="7" /&gt;
      &lt;/td&gt;
      &lt;td style="width:78px;"&gt;Est.Monthly Pmt
          &lt;input id="theResult" size="7" maxlength="7" name="result" style="width:75px" value="0" /&gt;
      &lt;/td&gt;
      &lt;/tr&gt;
  &lt;/table&gt;
  &lt;button type="button" id="calculate"&gt;Add Boxes!&lt;/button&gt;
  &lt;/div&gt;
  </code></pre>