Please help what is wrong, why false


#1

var cashRegister = {
total:0,
//Dont forget to add your property
add: function(itemCost) {
this.total += itemCost;
},
scan: function(item,quantity) {
switch (item) {
case "eggs": this.add(0.98 * quantity); break;
case "milk": this.add(1.23 * quantity); break;
case "magazine": this.add(4.99 * quantity); break;
case "chocolate": this.add(0.45 * quantity); break;
}
return true;
},
//Add the voidLastTransaction Method here
voidLastTransaction: function(lastTransactionAmount){
this.lastTransactionAmount += this.total;
console.log(lastTransactionAmount);
}

};

cashRegister.scan('eggs',1);
cashRegister.scan('milk',1);
cashRegister.scan('magazine',1);
cashRegister.scan('chocolate',4);

//Void the last transaction and then add 3 instead
cashRegister.voidLastTransaction();
cashRegister.scan('chocolate',3);
//Show the total bill
console.log('Your bill is '+cashRegister.total);


#2

In your voidLastTransaction Method
you will want to substract the _lastTransactionAmount from the total-amount.

this.total -= lastTransactionAmount;