Bongard problem 35

Which rule satisfies the 6 figures on the left but not the 6 figures on the right?

The Russian scientist M.M. Bongard published a book in 1967 that contains 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 and at Harry Foundalis site, and in the category ‘Bongard problems’ in the right margin of this page.

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.

1 to 9

1 to 9 is the name of a twitter account linked to https://maththinkblog.wordpress.com/. It uses several puzzle formats, one of them is this:
fill in the digits 1 to 9 all exactly once in this square. The digit 4 has already been given. The numbers along side the square are the sum of the numbers in the diagonal, row or column.

You can check your solutions 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.

Clocks

On 2018, june 29, I published a post with two clock problems. Here you find two more problems.

1) Clock 1^**/*****

2) Clock 2^**/*****

You can check your solutions here

New puzzles are published at least twice a month on Fridays. Solutions are published one or more weeks later. You are welcome to comment on alternate solutions, the level of difficulty, and so on.