# You Deserved It! Riddle: What is NaN but is a number?

#1

So, my code would fail this test because the cashRegester.total returns NaN. I know this because I started running some elements of the code I personally was adding through a console.log(). The weird thing is and why I'm lost here is because I didn't write anything that I am aware of that affects that total property of the register. And what really throws me for a loop is that I console.log()'ed typeof for the total returning NaN and lo and behold it says it's a number. Help?

``````function StaffMember(name,discountPercent){
this.name = name;
this.discountPercent = discountPercent;
}

var sally = new StaffMember("Sally",5);
var bob = new StaffMember("Bob",10);

// Create yourself again as 'me' with a staff discount of 20%
var me = new StaffMember ('Austin', 20);

var cashRegister = {
total:0,
lastTransactionAmount: 0,
this.total += (itemCost || 0);
this.lastTransactionAmount = 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;
},
voidLastTransaction : function(){
this.total -= this.lastTransactionAmount;
this.lastTransactionAmount = 0;
},
// Create a new method applyStaffDiscount here
applyStaffDiscount: function (employee) {
this.total -= this.total * (100 - employee.discountPercent / 100);
}
};

cashRegister.scan('eggs',1);
cashRegister.scan('milk',1);
cashRegister.scan('magazine',3);
// Apply your staff discount by passing the 'me' object
// to applyStaffDiscount
cashRegister.applyStaffDiscount('me');

// Show the total bill
console.log('Your bill is '+cashRegister.total.toFixed(2));

console.log(cashRegister.applyStaffDiscount('bob'));
console.log(cashRegister.total);
console.log(me.discountPercent);
console.log(typeof cashRegister.total);``````

#2

here:

``cashRegister.applyStaffDiscount('me');``

you call the applyStaffDiscount with as argument `'me'`, right?

so then we get:

``this.total -= this.total * (100 - 'me'.discountPercent / 100);``

the string `'me'` doesn't have a discount percentage? You should instead use your staff member (`me`), same for bob.

`'me'` is a string
`me` is a staff member

#3

Ooooooooh, but of course. I make this kind of mistake all the time. As soon as I finish with this js lesson, which is now, I'm going back through it just to study the exact syntax of all the things I learned. That fixed it, thank you.

#4