JSFiddle - React, Tailwind, and code Playground

HTML

<div id="readout">
    0
</div>
<div id="imagecontainer"> 
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20001.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20002.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20003.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20004.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20005.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20006.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20007.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20008.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20009.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20010.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20011.jpg" />
    <img src="http://www.megancullenphoto.com/img/documentary/cambodia/Megan%20Cullen%20012.jpg" />
</div>

CSS

img{
    position: relative;
    float: left;
    height: 500px;
    border: 0px;
}

#imagecontainer {
    position: relative;
    height: 500px;
    width: 100px;
    left: 0px;
    background-color: #555555;
}

JavaScript

var totalwidth = $("#imagecontainer > img").width();
$("#imagecontainer").width(totalwidth);
$("#readout").html(totalwidth);