Aug 1

## Geek/X Puzzle Hunt

Our friends at Geek_X, an Australian company for high-quality geek stuff, recently created a fun interactive puzzle hunt. To solve it, visit the link from the video below…

Oct 29

## Thoka’s Rebus 2

Can you figure out which word is depicted by this rebus?

The first image depicts a SEA. When you switch the third letter to C, you get SEC. The second image depicts RED. When you make the third letter a hard consonant, you get RET. The last two images depict a DIARY and DI (501 in Roman numerals). Therefore, you get:

SEC + RET + DIARY – DI = SECRETARY

Oct 27

## Creepy Beasties Inc.

At Creepy Beasties Inc., three of the most dreaded animals, a spider, a snake, and a rat, sat in their boardroom in silence while they awaited their boss. Then, Mr. Spider broke the silence.

“Isn’t it odd that our surnames match our species, yet none of our surnames match our own?”

The snake replied, “Yeah, but does anyone care?”

They sat in silence again…

Can you figure out the surname of each animal?

Since the snake replied to Mr. Spider, her surname can’t be neither Spider nor Snake. Therefore, the snake’s surname is Mr. Rat. Subsequently, Mr. Spider must be a snake, and finally, Mr. Snake must be a rat.

Oct 23

## Moving to a New House

A man was moving to a new house. He rented a moving truck, put all his belongings in it, and drove to his new place. He entered the garage with the truck and took all his belongings out of the truck. When he tried to exit the garage with the truck, he couldn’t. Why?

The empty truck was just slightly taller than the garage door. When it was packed with items, the truck’s height got lower, so the man could enter the garage. Once the items were unpacked, the truck was once again taller than door, so it couldn’t get out.

Oct 21

## Tropical Maze

Escape from the START to END in this tropical maze, created by Ben Uelk.

The solution is shown below.

Oct 19

## Two Lost Cards in a Deck

Below you can read the steps of a magic trick, as well as a video of its live performance. Your goal is to figure out how the trick is done, then perform it for your friends and challenge them to figure out the trick themselves.

1. Take out from your pocket a deck of cards, which is visibly shuffled.
2. Ask your first assistant to cut the deck, then take the top card from the bottom pile of cards and memorize it.
3. Ask your second assistant to take the next card from the bottom pile and memorize it.
4. Ask your first assistant to return his card back on the top of the bottom pile, then ask your second assistant to do the same.
5. Place the two piles of cards on top of each other and cut the deck multiple times.
6. Split the deck into two piles of cards, dealing consecutively one card on the left, then one card on the right, and so on, until you run out of cards.
7. Take one of the two piles of cards, look at it, and guess correctly what cards were chosen by your assistants.

How does the magic trick work? Below you can see a live performance of the magic trick from Penn and Teller’s show Fool Us.

The secret of the trick is to memorize the group of cards which are located in even positions and the group of cards which are located in odd positions in the original deck. An easy way for doing this is to split the cards into two groups, such that the cards in the first group are only spades and diamonds, and the cards in the second group are only clubs and hearts.

When the two assistants pick their cards and then return them back into the deck, the order of the cards is reversed. When you split the original deck into two piles (even after cutting it several times), each of the piles will contain a card which should not be there. For example, the group of spaes and diamonds will contain one clubs card, and the group of clubs and hearts will contain one diamonds card. These two cards are the ones which were picked by the assistants.

Oct 17

## Ten Lanterns

You have ten lanterns, five of which are working, and five of which are broken. You are allowed to choose any two lanterns and make a test which tells you whether there is a broken lantern among them or not. How many tests do you need until you find a working lantern?

Remark: If the test detects that there are broken lanterns, it does not tell you which ones and how many (one or two) they are.

You need 6 tests:

(1, 2) → (3, 4) → (5, 6) → (7, 8) → (7, 9) → (8, 9)

If at least one of these tests is positive, then you have found two working lanterns.

It all of these tests are negative, then lantern #10 must be working. Indeed, since at least one lantern in each of the pairs (1, 2), (3, 4), (5, 6) is not working. Therefore, there are at least 2 working lanterns among #7, #8, #9, #10. If #10 is not working, then at least one of the pairs (7, 8), (7, 9), or (8, 9) must yield a positive test, which is a contradiction.

With some case analysis, it is not hard to see that 5 tests are not enough.