무지 간단한 계산 / 합산 프로그램 짯는데 값이 안나와용.....ㅜ.ㅜ 오류만떠요.

 
<form name="f">
 
<table  border="0" cellspacing="0" cellpadding="0" width="900" height="1100" align="center" >
<tr>
 <td><table border="0" cellspacing="0" cellpadding="0" width="850" align="center"  class="table02">
    <tr>
        <td  colspan="2">
            <p align="right"><font color="red">&nbsp;(3년약정기준)</font> &nbsp;&nbsp;&nbsp;
        </td>
    </tr>
      <tr>
        <td width="150" align="center" bgcolor="#F7F7F7" height="40">
            <font color="#17365D">인터넷(비즈광랜)</font>
        </td>
        <td width="676" height="40">&nbsp;&nbsp;<INPUT  type=radio value=0 name="kind1" onclick="chk_ok(this.value)">신청안함
  
   <INPUT type=radio value=4 name="kind1" onclick="chk_ok(this.value)">소호(1 IP)
   <b><INPUT CHECKED type=radio value=1 name="kind1" onclick="chk_ok(this.value)">스탠다드(2 IP)</b>
   <INPUT type=radio value=2 name="kind1" onclick="chk_ok(this.value)">스탠다드(3 IP) &nbsp;&nbsp;
   <INPUT type=radio value=3 name="kind1" onclick="chk_ok(this.value)">스탠다드(4 IP) &nbsp;&nbsp;
        </td>
    </tr>
 </table>
<br>
 <table border="0" cellspacing="0" cellpadding="0" width="850" align="center"  class="table02">
    <tr align="center">
        <td width="150"  bgcolor="#E1E1E1">
            <font color="blue">구분</font>
        </td>
        <td width="150"  bgcolor="#E1E1E1">
            <font color="blue">월기본요금</font>
        </td>
        <td width="150"  bgcolor="#E1E1E1">
            <font color="blue">장비임대/단말기부담액</font>
        </td>
        <td width="141"  bgcolor="#E1E1E1">
            <font color="blue">월실납부액(VAT포함)</font>
        </td>
        <td  bgcolor="#E1E1E1" width="259">
            <font color="blue" >비 고</font>
        </td>
    </tr>
    <tr align="center">
        <td bgcolor="#F7F7F7" width="150">
            인터넷
        </td>
        <td width="150" >
            &nbsp;<input type="text" name="b1" id="b1" value="" size="15" class="button" readonly style="text-align:right">
        </td>
        <td width="150" >
            &nbsp;<input type="text" name="b2" id="b2" value="" size="15" class="button" readonly style="text-align:right">
        </td>
        <td width="141" >
            &nbsp;<input type="text" name="b3" id="b3" value="" size="15" class="button" readonly style="text-align:right">
        </td>
        <td width="259" >
           
                                <p align="left">3년 가입설치비무료/100M (특별추가할인)
        </td>
    </tr>
</table>
<script>  
function sum() { 

var f = document.f;  //젤 먼저...

var kind1 = f.kind1.value;  // 각 변수들에 입력된 값 넣어줌

var b1 = f.b1.value;
var b2 = f.b2.value;
var b3 = f.b3.value;

   

b1 = kind1 * 25000; 
b2 = b1+5000;
b3 = b1*1.1;
      

 

b1 =  Math.floor(b1/10) * 10 ;
b2 =  Math.floor(b2/10) * 10 ;
b3 =  Math.floor(b3/10) * 10 ;
f.b1.value = b1;  // 값 넣어줌.
f.b2.value = b2;
f.b3.value = b3; 
} 

 

 </script>