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JavaScript JavaScript Basics (Retired) Working With Numbers Numbers and Strings

Tobias Jackson
Tobias Jackson
9,758 Points
Posted by Tobias Jackson
Tobias Jackson
9,758 Points

i dont know what to do. i dont understand it?

Imagine you have 10 <div> tags on a web page. Each div is 190 pixels wide. Using the two variables in this script, create a new variable named totalWidth that multiplies the width by the numOfDivs variable. Because the width variable is a string, you'll need to use a JavaScript function to retrieve the number value.

app.js 
var width = '190px';
var numOfDivs = 10;
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="app.js"></script>
</body>
</html>
Jacob Mishkin
Jacob Mishkin
23,118 Points

What part of this question are you having trouble with.

sebastianlagerblad
sebastianlagerblad
5,083 Points

use parseInt to convert width into an intger

spoiler

var width = parseInt('190px'); var numOfDivs = 10;

var totalWidth = width * numOfDivs;

Tobias Jackson
Tobias Jackson
9,758 Points
Tobias Jackson
Tobias Jackson
9,758 Points

how? show me the code, pleas

sebastianlagerblad
sebastianlagerblad
5,083 Points

Edited my above comment

1 Answer

James Anwyl
.a{fill-rule:evenodd;}techdegree seal-36
James Anwyl
Full Stack JavaScript Techdegree Graduate 49,960 Points

Hi Tobias,

First thing it asks is to create a variable named totalWidth. We can do this like so:

var totalwidth;

Then we need to store the result of width * numOfDivs inside totalWidth:

var totalWidth = width * numOfDivs;

This will give us an error though, because we are trying to multiply a string and a number. We need to convert width into a number before we multiply it. Javascript has a method that can convert a string to a number, which was covered in this video.

Don't want to post the answer, but hopefully this will give you a push in the right direction. :)