Monthly Archives: July 2019

Playing card puzzles (1)


While waiting for my appointment with the dentist I thumbed through the magazines, looking for good puzzles. I had little hope of finding any more than a crossword or sudoku, but to my surprise I encountered a new format in the magazine plusonline. The magazine does have a website, as the name suggests, but I couldn’t find the puzzles there.

In all puzzles the problem is: which of the four cards at the bottom should replace the blue card?

Here are two puzzles in the same vein. I did make a small change: the original puzzle had rows of three cards, which I changed into cards rows of four cards.

1) Playing cards square nr 1***/*****

You can check your solution here

2) Playing cards square nr 2***/*****

You can check your solution here

New puzzles are published at least twice a month on Fridays. Solutions are published after one or more weeks. You are welcome to remark on the difficulty level of the puzzles, discuss alternate solutions, and so on. Puzzles are rated on a scale of 1 to 5 stars.

Be prepared for more puzzles of this type in a few weeks.

Bongard problem 36


Which rule satisfies the 6 figures on the left but is obeyed by none of the 6 figures on the right?
1)Bongard problem 10***/*****


In 1967 the Russian scientist M.M. Bongard published a book containing 100 problems. Each problem consists of 12 small boxes: six boxes on the left and six on the right. Each of the six boxes on the left conform to a certain rule. Each and every box on the right contradicts this rule. Your task, of course, is to figure out the rule.

You can check your solution here

You can find more Bongard problems here on this site and at Harry Foundalis’ site.

New puzzles are published at least twice a month on Fridays. Solutions are published after one or more weeks. You are welcome to remark on the difficulty level of the puzzles, discuss alternate solutions, and so on. Puzzles are rated on a scale of 1 to 5 stars.