# Space Mystery Magic Trick

### It's a card trick! No - It's a math trick! No - It's the Space Mystery Magic Trick!

The Space Mystery Magic Trick is actually a combination between a magic trick and a math trick. It's a great trick that will allow you to impress your audience, and you can also use it to demonstrate elementary algebra.

Free Magic Cards

Please download the FREE Space Mystery Printable Cards PDF file file in order to perform this trick. It is all set to print out on Avery white, two-sided, clean edge business cards (Avery #28878). Simply load two sheets of business card sheets and print them, flip them over in reverse order, and print again to get two sheets of printed cards. You may want to practice first on regular paper before using the business card sheets.

Performing the Trick

Start off with a stack of the Space Mystery cards you printed out, with half of them with the alien side facing up. The trick will work with any number of even cards, but I would suggest using no more than 12. In this demonstration, I will be using 12 cards.

Position the cards on a table to show your audience that half of the deck are showing the alien side:

Now shuffle the cards until the cards are very well randomized, and then lay half of them on the table. You may get something that looks like this:

Now, using slight of hand, flip the cards (it helps here to transfer the remaining cards to your other hand while you do the flipping) while saying some magic words (eg., presto - chango!). Now lay out the cards under the first row of cards, and tell the audience that the cards have magically transformed such that both sets have the same number of aliens facing up. They probably will not be in the same order in your hand - simply lay them out such that the alien cards are placed under the alien cards, and the space-only cards are placed under the space-only cards:

Why the Trick Works

Here is an algebraic explanation of why the trick works. This is great to show your students or kids in order to show them an application of algebra.

You start off with 6 alien cards face-up

After the cards are shuffled, they are split into 2 stacks of cards, 6 cards each

Let the number of alien-up cards in stack 1 = A

Then the number of alien-up cards in stack 2 must = 6-A

Now, with a some thought you can determine the number of space-only cards that remain in stack 2. This turns out to be 6 minus the # of alien cards, or:

6 – (6 – A), which is equal to A

So, if you now flip stack 2, the space-only cards (equal to A) now become alien cards – the same number of alien cards in stack 1!