JSFiddle - React, Tailwind, and code Playground

HTML

<div class="mydiv">

    <img src="http://www.francodacosta.com/wp-content/uploads/resize_200_150.png">

</div>
<div class="mydiv">

    <img src="http://www.thew2o.net/files/GlobalForumonOceans_oceanleadership.org_.jpg">

</div>
<div class="mydiv">

    <img src="http://oceaninmotion.wikispaces.com/file/view/ocean.jpg/243726647/ocean.jpg">

</div>

CSS

.mydiv
{
    width:200px;
    height:150px;
    border: 1px solid red;
}

.mydiv img 
{
    width:100%;
}