var num_ads=11;

//Calculate a random number based on the number of ads
var rand=Math.round(Math.random()*num_ads)

if (rand==0) {
	rand_ad=1;
} else {
	rand_ad=rand;
}

//Each Ad image must go somewhere so here is the array containing the link for each ad

var ad_array=new Array(
"",
"http://www.educationamerica.net",
"http://www.educationamerica.net",
"http://www.educationamerica.net",
"http://www.educationamerica.net",
"http://www.educationamerica.net",
"http://www.educationamerica.net",
"http://www.educationamerica.net",
"http://www.educationcanada.com",
"http://www.educationcanada.com",
"http://www.educationcanada.com",
"http://www.educationcanada.com"
);


function ad_write() {

	document.write("<a href=\""+ad_array[rand_ad]+"\"><img src=\"http://www.educationworld.net/ads/ewn"+rand_ad+".jpg\" width=\"130\" border=\"0\" alt=\"\"></a><br>");

}