ShmoopTube

00:03

Here’s a question to provide your daily dose of shmoop…

00:06

Q-Bert is having a staircase built… and of course he’s using cubes to do it.

00:11

The blueprint below consists of 1 inch cubes. 

00:17

What is the total volume of the figure?

00:20

And here are the potential answers...

00:25

This one’s all about the visualization – and we have 3 layers of steps here to calculate.

00:30

The bottom layer here is 1 2 3 deep by 1 2 3 4 wide;

00:36

The middle layer here is 1 2 deep by 1 2 3 4 wide

00:40

And the top layer is just 1 deep by 4 wide.

00:43

The problem asks us to add the cubes to get the volume – and since they are each just

00:47

1 by 1, the arithmetic should be pretty easy.

00:52

The volume of a cube is simply base times height times depth… and note that they are

00:57

described in terms of CUBIC inches.

01:00

Like they could've given you some curve ball like saying square inches in the answer set,

01:04

and boy, that would be wrong.

01:05

So our total then is 4 times 3 for the base layer, which is 12…

01:10

plus 2 times 4 for the 2nd layer, which is 8… and 4 times 1 for the top layer… which is 4.

01:17

Add ‘em all up and we have 12 plus 8 plus 4 to give us... 24.

01:21

Our answer is D.

01:22

As in...

Full Transcript