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

Denis Mudrov
PLUS
Denis Mudrov
Courses Plus Student 541 Points

It's asking me to create a variable named totalWidth and I did but it's saying that my code is incorrect.

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

4 Answers

Steven Parker
Steven Parker
230,248 Points

Here's a few hints:

  • when they say "Using the two variables in this script" they mean use them by name
  • you will use these in the calculation but you won't reassign either of them
  • you calculation will require both variables
  • only one needs to be converted to a number

So here is the code they gave you in the question:

var width = '190px';
var numOfDivs = 10;

And the question asks you to create a new variable called totalWidth which has the value of the width and numOfDivs variables multiplied together. Now, note that the width variable has a value of '190px' in a string. If we just use the string value in our new totalWidth variable, it will return an error, because you cannot multiply a number by the string.

Instead, we need to use a special function called parseInt(). The parseInt() function accepts a variable with a string value that contains a number inside the parentheses. So, after creating your new variable totalWidth, assign a value of parseInt() and multiply that by the numOfDivs, and that should give you the correct answer.

I hope that has helped.

Denis Mudrov
Denis Mudrov
Courses Plus Student 541 Points

Do I just do, var totalWidth = parseInt(190px) * numOfDivs ?

Denis Mudrov
PLUS
Denis Mudrov
Courses Plus Student 541 Points

I'm still having problems understanding this assignment. Can someone tell me the exact formula I have to type in. I'm pretty sure I've tried out any formula I could possible think of and I'm still stuck.

You are close. You do not need to specify 190px again, you have already stored that in the variable width. Just replace the parseInt() value with the variable width, and that should do it.

Steven Parker
Steven Parker
230,248 Points

Try applying the hints I gave you and if you still haven't passed, post what you have after the changes.

Christian Leanza
Christian Leanza
3,101 Points

This is the correct code & should help you solve the problem!

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