Riddles with matrices

Puzzles, riddles, brain teasers, conundrums, logic questions in pictures. Here all tasks are presented in the form of various matrices. Most often these are rectangular matrices that have external rows and columns. In these logic puzzles, brain teasers and conundrums, the columns and rows affect the contents of the matrices. 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 - 17
In this difficult puzzle-conundrum you need to figure out the rule for placing numbers in the cells of the outer and inner ring. You then need to choose the correct number option from those below to replace the question mark.
Correct answer = 5.
There are four pairs of opposing cells. For example: 1, 4 and 5, 2. The sum of the numbers of the outer cell and the opposite inner cell is equal to the sum of the numbers of the inner cell and the opposite outer cell. In our example it will be like this: 4+2 = 5+1. Another example: 3, 10 and 7, 0. As a result: 3+7 = 10+0.
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