Hi Erice ,
I have Update

need ver : 4
I would like to add new Feild = feild3
result1 will not affected with feild 3
only result2 will be same math the only Different is make feild1+feild3.
i traed to use your previos cod after edite but it dosent work with me
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script>var jQ = $.noConflict(true);
jQ(document).ready(function(){
// ver 3
jQ("#item3").css("display", "none");
jQ("#item4").css("display", "none");
jQ("input[name='fild1'],input[name='fild2']").keyup(function(){
var fild1 = parseFloat(jQ("input[name='fild1']").val());
var fild2 = parseFloat(jQ("input[name='fild2']").val());
if(jQ.isNumeric(fild1) && jQ.isNumeric(fild2) && fild1 !='' && fild2 != '' ){
var result1 = Math.ceil(((fild1+fild2 )-(fild1*0.04))/0.375);
var result2 = 0;
jQ("input[name='result1']").val(result1);
if(((fild1+fild3)*0.05) <=8){
result2 = Math.ceil(8/0.375);
}
else{
result2 = Math.ceil(((fild1+fild3)*0.05)/0.375);
}
jQ("input[name='result1']").val(result1);
jQ("input[name='result2']").val(result2);
}
else{
jQ("input[name='result1']").val('');
jQ("input[name='result2']").val('');
}
});
});</script>