Apr 13, 2007

## Brain Teaser: Dr. Nasty’s Giant Cube

By: Caroline Latham

Here is another mind-bender created by Wes Carroll for the SharpBrains readers.

Presenting …

**Dr. Nasty’s Giant Cube**

**Difficulty:** HARDER

**Type:** HYBRID (Logic/Spatial)

**Question:**

The diabolical Dr. Nasty has turned his Growth Ray on a perfect cube that used to measure one foot on a side. The new larger cube has twice the surface area of the original. Find the volume of the larger cube.

Click to read Hint #1.

Click to read Hint #2.

Click to read Hint #3.

Click to read Hint #4.

Click to read the Solution and Explanation.

Damn, this is propably the easiest puzzle you have ever posted here.

Masa, I’m glad to hear you’re sharp enough to get this one so quickly! Not everyone else has. We’ll post another one tomorrow – come back and see how you do!

I don’t like the explanation becasue it relies on rules of thumb. It’s simlple to go to the fundamental equations for SA and V. Each side is 1 X 1. Times 6 sides = 6. Double that is 12. Solve for side length gives Ã¢Ë†Å¡2. V = side length cubed. 2*Ã¢Ë†Å¡2.

Sandman,

Thanks for another, very valid explanation!

giggity.

It is annoying to have to download the answers and hints to Word. Can’t you make it part of the website?

Hello Alana, we stopped using this Word system to display answers, given feedback like yours. The answers to most teasers are now easier to find. Thanks.

To use the basic volume equation V = H x L x W,

V = Ã¢Ë†Å¡2 x Ã¢Ë†Å¡2 x Ã¢Ë†Å¡2

I agree with Alana, it is very annoying to download the hints and answers and usually I don’t. It would be much better if you could just click and read!!

Hello Sheri, OK, let us think how to make it easier to check the answer. Thanks for the feedback.

Yea i found this one very easy.

Just create another linked “webpage” for the answer….the download is annoying.

i love dr. nasty =)

technically you cant double a ‘perfect’ cube…the answer is irrational…triple a cube yes , never double…well i think so anyway

The older side is 1 Foot.

As the new area of one side is now 2 square feet, then one side becomes âˆš2 feet (or 1.414 feet). Now the Volume is:

âˆš2 x âˆš2 x âˆš2 = 2âˆš2 = 2.828 cubic feet.