error you get is because the 'if' statement is incorrect. your answer field is named in your code 'total2' so why are you writing "calculate". besides if you want to refer to a text field you gotta have 'name' or 'id' attribute for the <input> element. don't forget about the 'type' attribute either. if you want to check whether your answer is greater than 80 or less, you have to do it by invoking the function because when your browser window loads, you have your form elements empty so javascript can't tell if the result is greater or less than 80. just check out how i rewrote the code...
<html>
<head>
<title>Trade Program</title>
</head>
<body>
<center><h1>Is Your Trade Legit???</h1></center>
<SCRIPT language=JavaScript>
<!--
function getPercentage() {
a = parseFloat(document.myform.c.value); //make sure that variable 'a' is an number
b = parseFloat(document.myform.d.value); //same here
c = a/b;
d = c*100;
document.myform.total.value = d;
if(d>=80 && d<=100) answer.innerHTML = "answer is between 80% and 100%";
else if(d>=70 && d<=80) answer.innerHTML = "answer is between 70% and 80%";
else if(d>=60 && d<=70) answer.innerHTML = "answer is between 60% and 70%";
else answer.innerHTML = "is somewhere between 0% and 60%";
}
//-->
</SCRIPT>
<FORM name="myform">
<TABLE cellSpacing=1 cellPadding=1 border=1>
<TBODY>
<TR>
<TD align=middle colSpan=3>
<B>Trade Calculator</B>
</TD>
</TR>
<TR>
<TD>
<INPUT type="text" size=5 name="c"> is what percent of
<INPUT type="text" size=5 name="d">?
</TD>
<TD>Answer: <INPUT type="text" size=5 name="total"> %
</TD>
<TD>
<INPUT onclick="getPercentage();" type=button value="Calculate" name="calc">
</TD>
</TR>
<TR>
<TD align=middle colSpan=3>
<INPUT type=reset value=Reset>
</TD>
</TR></TBODY></TABLE></FORM>
<span id="answer">
</span>
</body>
</html>
:D:D:D:D:):)


the genuine genius