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JavaScript JavaScript Basics (Retired) Working With Numbers Doing Math

mike howie
mike howie
1,953 Points

Does JavaScript follow the rules of operation?

var profit+= salesTotal - wholesalePrice * quantity;

script.js
var wholesalePrice = 5.45;
var retailPrice = 9.99;
var quantity = 47;
var salesTotal = retailPrice * quantity;
var profit += salesTotal - wholesalesPrice * quantity;
index.html
<!DOCTYPE HTML>
<html>
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  <title>JavaScript Basics</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

2 Answers

Jason Anders
MOD
Jason Anders
Treehouse Moderator 145,860 Points

Hey Mike, Julian is right about the +=.

But to answer your question, yes, JavaScript does follow the rules of operation.

Keep Coding. :)

Julian Aramburu
Julian Aramburu
11,368 Points

Hi! Why are you using the += operator? When you create a new variable you must use the = sign to set the value of that variable... in that case the variable profit is a new one so first you must asign a proper value before using that operator over it.