Mathematical puzzles

Puzzles, situation puzzles and recreational mathematics.

situation puzzles and recreational mathematics. Neuron juice

Neuron juice.

The important thing is not to stop questioning. (Albert Einstein.)

Math Puzzles

In this site you can find a selection of the most popular riddles and situation puzzles. Obviously, neither are here all who matter nor they matter all who are here. Some of them have been taken from the missing Snark list; others from books and other have been on my mind for a long time.


Every suggestion will be appreciated and included in this list.


Two of the riddles deserve special treatment, The riddle of the ages and the piano student is the one I always propose as a challenge. The other one is "Einstein's puzzle"  —if you don't know it yet, I highly recommend it.


Riddles and situation puzzles are mixed because of the difficulty of dividing them correctly into two independent groups, as some of them could be included in both groups.




22.- Would you be able in only 15 seconds to answer the question ?


What is greater 36% of 67 or 67% of 36?


-- Solving the riddle --



21.- In an extraordinary battle, at least 70 % of the combatants lost an eye ; 75% one ear , at least 80 % lost a hand and a leg 85 % .

How many , at least they lost the four bodies ?


-- Solving the riddle --



20. Two pastors spoke :

- Why do not you give me one of your sheep , so we have the same amount ?

To which his friend replies :

- Better give me one of yours and I'll double the sheep you

How many sheep had each?


-- Solving the riddle --



By José De La Cruz, Tucumán (Argentina)


19.- How do we get to twenty , adding one of us, nineteen ?


-- Solving the riddle --



18.- Terence is a gambler who has money when it plays dice .

He always does the same way : win or lose, bet half the money you have ; the second play , bet half the money you have time; on the third play , half of what he has after the second ; and so on.
One evening was 16 euros and played 6 times , won three and lost three others.
How much money runs out?


-- Solving the riddle --



17.- In a slaughterhouse boss tells the employee :

You have to kill these 30 sheep in 15 days , killing at least one per day and always odd number .
Can the employee 's bidding your boss?


-- Solving the riddle --



Sent by ROJO Alejandro, Lausanne (Switzerland).

16.- Among cows, sheep and chicken.

A master gave his servant 500 dollars for him to go to the market and buy 100 heads of cattle. He had to buy cows, sheep and chicken and spend all of the 500 dollars.

Once at the market, he realizes cows cost 25 dollars, sheep 5 dollars and chicken a quarter.

How many heads of cattle of each kind did he buy?





Sent by Bernardo Escobosa.

15.- A traveler is captured by some cannibals and they tell him:

If you tell a lie we will kill you slowly and if you tell a truth we will kill you quickly.

What does he say not to be killed?





14.- Three brothers divide their father's legacy, that is composed of 35 horses. In his will, the father wrote that the oldest brother would keep half the legacy, the middle brother would keep a third and the youngest brother would keep a ninth.

As the divisions were inexact, the brothers couldn't come to an agreement, so they decided to ask an old mathematician who proposed what follows:

Given that 35 horses can't be exactly divided by 2 nor by 3 nor by 9, I give you mine. Now you have 36 horses, so you all come out ahead. As the oldest, you will take 36/2, that's it, 18 horses. As the middle, 36/3, that's it, 12 horses. And you as the youngest, following the wish of your father, a ninth, 4 horses.

Now you all have your legacy, and as 18+12+4=34, there are two horses left, so I get mine back and keep the other one as a payment for solving your problem.


How is this possible?


-- Solution of the riddle --



13.- A jeweler is given 4 pieces of chain with 3 links each one, and is asked to join them to create a bracelet.

When preparing the estimate, the jeweler calculates he has to solder four link, each one costs one euro so the total price would be four euros. However, the customer doesn't agree and tells him who to do it just solding three links.

How did he do it?


-- Solution of the riddle --