<script language="JavaScript">
function chk(){
var a1=parseFloat(document.frm.a.value);
var a2=parseFloat(document.frm.b.value);
var a3=parseFloat(document.frm.c.value);
var a4=(a1*a2)/100*a3/12;
var a5=a1+a4;
document.frm.d.value=a4;
document.frm.e.value=a5; //---- เปลี่ยนเอาจะ + - * /
}
</script>
<script language="JavaScript">
function chk(){
var a1=parseFloat(document.frm.a.value);
var a2=parseFloat(document.frm.b.value);
var a3=parseFloat(document.frm.c.value);
var a4=(a1*a2)/100*a3/12;
var a5=a1+a4;
if(isNaN(a4)){
document.frm.d.value=0;
}else{
document.frm.d.value=(a4).toFixed(2);
}
if(isNaN(a5)){
document.frm.e.value=0;
}else{
document.frm.e.value=(a5).toFixed(2);
}
}
</script>