I'd suggest a much easier way of going about this problem though, rather than having to create 100 variables, you can just perform a loop.
HTML Code:
<SCRIPT LANGUAGE="javascript">
function Gradeit()
{
var Answers=new Array(2,1,3,1,4,1,2,1,3,4,3,2,4,3,1,4,2,4,1,2,2,4,3,4,3,4,1,1,3,3,2,3,4,1,1,4,2,1,1,1,4,3,4,4,3,1,2,3,3,3,1,4,2,3,2,3,3,4,2,3,4,2,1,4,1,3,1,1,3,1,2,3,4,2,1,3,3,4,3,4,1,2,3,4,3,1,1,2,3,1,4,1,4,2,2,2,2,4,2,1);
var score=0;
for (i=0;i<100;i++) {
if (Answers[i] == document.forms[0].elements[i].selectedIndex) score++;
}
alert("You scored " + score + "%");
}
</SCRIPT>