Tryit Editor v1.7

Source Code:

Result:

<!DOCTYPE html>
<html>
<head>
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js">
</script>
<script>
$(document).ready(function(){
  $("button").click(function(){
    $("div").width(function(n,c){
    return c-200;
    });
  });
});
</script>
</head>
<body>

<button>Decrease width of div with 200 px.</button>
<br><br>
<div style="height:100px;border:4px solid;"></div>

</body>
</html>

Edit the code above and click "Submit Code" to see the result.

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Source Code:	Result:
<!DOCTYPE html> <html> <head> <script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"> </script> <script> $(document).ready(function(){ $("button").click(function(){ $("div").width(function(n,c){ return c-200; }); }); }); </script> </head> <body> <button>Decrease width of div with 200 px.</button> <br><br> <div style="height:100px;border:4px solid;"></div> </body> </html>
Edit the code above and click "Submit Code" to see the result.	W3Schools.com - Try it yourself