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JavaScript

Posted by Arjun Agarwal
Arjun Agarwal
4,743 Points

Hi! could someone tell me where I'm going wrong

Question: Imagine you have 10 images on a web page. Each image is 190 pixels wide. Using the two variables in this script, create a new variable named totalWidth that multiplies width by totalImages. Since the value of width is a string, you'll need to use a built-in JavaScript function to retrieve the number value.

Answer:

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

Mod edit: added code markdown. Check out the "markdown cheatsheet" below the comment box for syntax examples to help with code readability on the forum.

1 Answer

Cameron Childres
Cameron Childres
11,820 Points
Cameron Childres
Cameron Childres
11,820 Points

Hi Arjun,

Your only issue is when you pass width to parseInt(). Since width is in quotes you're passing the string "width" as opposed to the variable. Remove the quotes and you're good to go.

For a deeper dive you could look at the documentation for parseInt(). Under return value:

NaN when ... the first non-whitespace character cannot be converted to a number.

parseInt("width") sees the "w" first, can't convert it to a number, and returns NaN

Arjun Agarwal
Arjun Agarwal
4,743 Points

Thank you so much!