Classics of Recreational Math

The classical recreational math authors are Lewis Carroll,  Henry DudleyMartin GardnerSam Loyd, and Yakov Perelman.

This an example of classical math puzzles: :

(102 + 112 + 122) – (132 + 142) = ?

The picture “Mental Count” of Russian painter Nikolay Bogdanov-Belsky contains the simple calculation. Image source : Wikipedia



The logic puzzle almost everyone gets wrong

This is a very famous logic problem:

“Jack is looking at Anne, but Anne is looking at George. Jack is married, but George is not. Is a married person looking at an unmarried person?

  • A: Yes
  • B: No
  • C: Cannot be determined”


According to the Keith E. Stanovich in Scientific American more than 80 percent of people choose C, which is not the correct answer. The correct answer is A. Why?

This is another example of a similar problem:

There are only two handshakes in a meeting: John shakes hands with a person, this person shakes hands with Anna. Does a man shake hands with a woman in the meeting?


Project Starters

Challenging puzzlers to create a positive attitude to real projects.

Everyday Geek Questions

What happens once in a minute, twice in a week and once in a year?


I will be X years old in year X2. How old am I?


How many planes of symmetry does a cube have?


“1” costs $10. “20” costs $20. How much does “100” cost?


The Importance of Recreational Math

“The body of recreational mathematics that Mr. Gardner tended to and augmented is a valuable resource for mankind.” –

Aplusclick project tries to destroy the border between the Common Core and the Recreational Math.

Liar’s Math

Aplusclick Pinocchio

Pinocchio lies

When Pinocchio lies, his nose gets twice as long. When he tells the truth, his nose gets 1 cm shorter.

Today, his nose was 1 cm long in the morning, and it is 100 cm long in the evening.

What is the least possible number of times he opened his mouth today?

True and Random

Two gods  are called True and Random. True always speaks truly and Random speaks randomly truly or falsely. You don’t know who is who.

Determine the identities of the gods by asking yes-no questions; each question must be put to exactly one god.aplusclickgods

Adapted from G. Boolos. ‘The hardest logic puzzle ever’, The Harvard Review of Philosophy (6), 1996.


You find the answers to the questions in Grade 12 questions at

Crazy Puzzle

What number and why?Aplusclick crazy puzzle

Wittygon – Game and Math Lesson

aplusclickWittygonAplusclick has just launched Wittiygon. It is a mix of Math practice and a logic game.

icon-173-tile Aplusclick Logic Puzzle Wittygon is a free educational game for Very Intelligent People (VIP) in grades one through twelve and smart adults.

The game is free and ad-free.

 What is the story about?

In the Wittygon planetary system, the aim is to move a planet to a nearest neighbour in order to exchange positions. Match 4 or 5 planets in a row to win stars.  You win additional points if you correctly answer IQ Bonus Questions. The questions will be automatically adapted to your skills and motivation. The collection of the questions includes more than 400 logic questions, which don’t ask for special mathematical knowledge.

Where can you play?

Online: ,   iPhone or iPad,    Android:

online aplusclickAppsStore AplusclickGooglePlay

Enjoy the challenge – become clever!


Mathematically Correct Way to Cut a Cake

What is wrong with cutting a cake? We always do it in a wrong way. What is better way? Alex Bellos gives the answer.

Mathematical Problems of Love

Are there math problems of Love. Certainly, there are many of them. The theme is very important for teenagers.Professional dancers

  • What are chances of being chosen?
  • How long do gentlemen wait ladies?
  • How many roses are needed?
  • How much do I spend for a present?
  • How Gerry must to play so that Jane always wins?
  • How to share the family income?
  • How to manage family projects?

There are many examples of such simple questions and answers at the page


Gerry Geek’s love story in form of math problems is passionately described in his book at Amazon.

Hannah Fry’s TED Talk on the subject: