Looking through the code written by Indians ...

function calculate_price (formName, fieldName0, fieldName1, fieldName2, fieldName3, fieldName4)
{
var doc = 'document.';
var input0 = parseFloat (fieldName0);
var input1 = Trim (eval (doc + formName + "." + fieldName1 + ". value"));
var input2 = Trim (eval (doc + formName + "." + fieldName2 + ". value"));
var input3 = Trim (eval (doc + formName + "." + fieldName3 + ". value"));
var input4 = Trim (eval (doc + formName + "." + fieldName4 + ". value"));
if (input1 == '')
{
var tot_price = 0;
}
else
{
var tot_price = parseFloat (input0) * parseInt (input1);
}
var net_price = tot_price + parseInt (input3);
eval (doc + formName + "." + fieldName2) .value = tot_price;
eval (doc + formName + "." + fieldName4) .value = net_price;
}

And fieldName2 and fieldName4 are text boxes with such funny attributes:
style = "background: none; border: hidden; color: #FFFFFF; font-weight: bolder; "readonly