<div id="container">
  <div id="relative">
    <img src="https://i.imgur.com/odWztph.jpg" id="absolute" width="150px" height="auto" />
  </div>
</div>

div {
   box-sizing: border-box;
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
}
#container {
  width: 960px;
  margin: 0 auto;
  background-color: #e6e6e6;
  border: 1px solid #333;
  padding: 15px;
}

#relative{
  width: 100%;
  border: 1px solid #333;
  background-color: red;
  height: 300px;
  position: relative;
}
#absolute {
  position: absolute;
  right: 0;
  bottom: 0;
}