Наверно должно быть так:
function calcTotal() {
var weight = 0;
for ( var i = 0; i < form.weight.length; i++) {
weight += form.weight[i].checked * +form.weight[i].value;
}
var price = +form.price.value;
var deliveryPrice = 0.1 * price;
form.pricedeliv.value = deliveryPrice;
form.dostavkas.value = weight;
form.itog.value = weight + price + deliveryPrice + huyPoimiChe;
}
