Riddles with sequences

Puzzles, riddles, brain teasers, conundrums, logic questions in pictures. There are sequences created according to some rules. In these puzzles, brain teasers and conundrum you need to continue the sequence by choosing one of the given answer options. To check your answer, click on the «Answer» button located below the task. After this, the correct answer and explanations will appear. Below you can select other questions on this topic. Typically each topic has 20 questions or more. At the same time, the complexity of logical problems gradually increases. First there will be easy questions, then medium, then difficult. Try to complete tasks as quickly as possible.
Question - 15
This is a brain teaser. There is a sequence with eight columns arranged, with three geometric shapes in each column. Two columns are hidden behind brown rectangles. You need to figure out the rule in this sequence and replace the column with question marks with the correct answer.
Correct answer = 6.
Here 7 geometric objects are shown sequentially. Their order goes from top to bottom. Each time, only 3 objects that make up one group of objects are shown. With each step to the right, the order of objects shifts one position from top to bottom. To make the task more difficult, two additional groups of objects were hidden. All of them can be seen below in the image. To answer correctly, you need to see that the bottom object of some group is the same as the top object in the group located two positions to the left. The top two objects of some group are the same as the bottom two objects in the next group.
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