NumberOfImagesToRotate = 27;

FirstPart = '<img src="random/r';
LastPart = '.jpg" width="120" height="90">';

function printImage1() {
var r = Math.ceil(Math.random() * NumberOfImagesToRotate);
document.write(FirstPart + r + LastPart);
}
function printImage2() {
var r = Math.ceil(Math.random() * NumberOfImagesToRotate);
document.write(FirstPart + r + LastPart);
}