ShmoopTube

00:03

Here’s an unshmoopy question you’ll find on an exam somewhere in life…

00:07

The side lengths of the box shown below have been labeled.

00:11

What is the total surface area of the box?

00:15

And here are the potential answers...

00:19

This question is testing whether we can visualize. And… well… think.

00:23

In the case of this box, we know it has 6 sides, or 3 pairs of equal sized sides.

00:32

Here, here, and here…

00:35

Don’t look behind your PC, that's not going to help.

00:38

So to get the area we can just calculate the surface area of the sides we see –

00:44

then double ‘em. Like the gum.

00:47

Since we know that surface area is just base times height, side A here is 7 by 3.5 inches…

00:54

or 24.5 square inches.

00:59

Side B here is 3.5 times 3… or 10.5 square inches

01:07

And Side C here is 7 times 3 inches… or 21 square inches.

01:11

We can add the 3 sides – 24.5 plus 10.5 plus 21 and we get 56

01:18

for HALF the box’s surface area.

01:21

Now we double it and we get 112 – so it’s answer D.

01:27

As in… “Double the pleasure, double the fun.”

Full Transcript