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JavaScript JavaScript Basics (Retired) Working With Numbers Doing Math

mike howie
mike howie
1,953 Points
Posted by 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 145,858 Points
Jason Anders
Jason Anders
Treehouse Moderator 145,858 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
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.