<html>
<head>
  <title>Div example</title>
</head>
<body>

<style type="text/css"> 
.container{
  float: left;
  clear: left;
  border: 1px dotted;
}

.left {
  float: left;
  width: 120px;
  padding: 10px;
  border: 1px solid;
}

.right {
  float: right;
  width: 120px;
  padding: 10px;
  border: 1px solid;
}
</style>

<div class="left">
  1
</div>

<div class="container">
  <div class="right">
    2
  </div>
</div>

</body>
</html>