Riddles with transformations

Puzzles, riddles, brain teasers, conundrums, logic questions in pictures. There are questions here with various types of transformations of geometric images. In these logic tasks, puzzles and brain teasers, transformation is indicated by an arrow from left to right. 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 - 10
In this brain teaser, on the left side there is a triangle with a dot inside. This image transforms into a circle on the right. Find out the principle of this transformation and indicate the correct answer for the bottom line.
Correct answer = 5.
The dots inside the triangles show the size of the circle that will be created after the arrow. The dots show the center of the circle. The outline of this circle should touch the top and bottom of the triangle. The execution of all options is shown below. The further the point is from the tip of the triangle, the larger the circle will be. Therefore, the fourth line should produce a circle smaller than the second line, but larger than the third line.
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