<!DOCTYPE html>
<html lang="en-US">
<body>
<script>
var numObj = 12;
var bin = numObj.toString(2);
var oct = numObj.toString(8);
var hexa = numObj.toString(16);
document.write("binary 12 ="+ bin);
document.write("<br>octal 12 = "+ oct);
document.write("<br>hexa 12 = "+ hexa);
</script> </body>
</html>