title: Unable to bind expressions with input values
body: <p>I was learning <a href="http://www.w3schools.com/angular/angular_intro.asp" rel="nofollow">AngularJS</a>. To practically fiddle with it, I was trying to create a basic calculator which read values from input box, does basic calculation and give output.</p>
  
  <p><a href="http://jsfiddle.net/xameeramir/tub4z76b/" rel="nofollow">Here</a> it is:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
  <div class="snippet-code">
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"&gt;&lt;/script&gt;
  &lt;div data-ng-app=''&gt;
      
      &lt;p&gt;Enter first number: &lt;input type="number" ng-model="input1"&gt;&lt;/p&gt;
          &lt;p&gt;The number you entered is &lt;mark ng-bind="input1"&gt;&lt;/mark&gt;&lt;/p&gt;
      &lt;p&gt;Enter second number: &lt;input type="number" ng-model="input2"&gt;&lt;/p&gt;
          &lt;p&gt;The number you entered is &lt;mark ng-bind="input2"&gt;&lt;/mark&gt;&lt;/p&gt;
  
          &lt;p&gt;
              Subtraction: {{ (Property.input1|number) + (Property.input2|number) }}
          &lt;/p&gt;
  
          &lt;p&gt;
              Sum: {{ (Property.input1|number) + (Property.input2|number) }}
          &lt;/p&gt;
      
          &lt;p&gt;
              Product: {{ (Property.input1|number) * (Property.input2|number) }}
          &lt;/p&gt;
          
          &lt;p&gt;
              Division: {{ (Property.input1|number) / (Property.input2|number) }}
          &lt;/p&gt;
          
  &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>The values doesn't seem to be automatically getting calculated. Can someone guide?</p>