this.setrandomcontent = function(){

    var pause = 3000; // define the pause for each tip (in milliseconds) 
    var length = $("#didyouknow li").length; 
    var temp = -1;        

    this.getRan = function(){
        // get the random number
        var ran = Math.floor(Math.random()*length) + 1;
        return ran;
    };
    this.show = function(){
        $("#didyouknow li").hide();    
        $("#didyouknow li:nth-child(" + getRan() + ")").fadeIn("fast");        
    };
    
    show();
    
};

$(document).ready(function(){    
    setrandomcontent();
});