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JavaScript JavaScript Numbers Working with Numbers Numbers and Strings

Do I multiply by the totalWidth? Or do I add another variable with the purseInt stating the amount?

script.js
const width = '190px';
const totalImages = 10;

const totalWidth =  width * totalImages;
const num = 1900;
const webValue = parseInt(1900);

1 Answer

Hi Alonzo!

Your goal is to multiply the width by totalImages.

width, however, is a CSS string property value, so for the math to work properly you have to cast/convert width to a number ( using parseInt() ).

So the code is actually this simple (and passes)

const width = '190px';
const totalImages = 10;

const totalWidth =  parseInt(width) * totalImages;

Note: parseInt, in this case, casts/converts '190px' to 190, thus after the multiplication, totalWidth will be 1900.

(190 * 10) == 1900, in other words...

BTW, if you really want to see it, open your devtools and find the console.

At the prompt type:

> const width = '190px';

And hit enter. It will return undefined, which is fine.

The type:

> console.log( parseInt(width) );

It will return:

190
undefined

You can ignore the undefineds (undefined is the return value of console.log() regardless of what it logs)

(If you type 2 + 2 at the prompt it will return 4, not undefined).

More info:

https://stackoverflow.com/questions/24342748/why-does-console-log-say-undefined-and-then-the-correct-value

I hope that helps.

Stay safe and happy coding!