var imglist = new Array(
"../40.jpg","../41.jpg","../42.jpg","../43.jpg","../44.jpg","../45.jpg","../46.jpg","../47.jpg","../48.jpg","../49.jpg");
var selectnum = Math.floor((Math.random() * 100)) % imglist.length;
var output = "<img src=" + imglist[selectnum] + ">";
document.write(output);