Well, we are continuing with what is x series.
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| 3 11 9 |
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|
v
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| 8 17 5 |
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|
v
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| 9 17 2 |
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|
v
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| 6 22 x |
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As the arrows indicate the box below, there must connection with the boxes. Try to find x through applying a method that is valid for all the boxes.
I tried to solve it but to no avail. I added all the numbers in the boxes; 3+11+9=23, 8+17+5=30, 9+17+2=28 and no way to go, no result, no logical numbers here. In the 2nd and 3rd boxes, the center number is 17, and 1st number increases by 1 but the last number decreases by 3, I still couldn't find any possible algorithm there.
Possible answer is 8.
Source: The question is asked in YTUYOS 2017 booklet A, question no: 58. These are the questions asked in university entrance exam for international students in Turkey. These types of questions should not take more than 2 minutes to solve and generally they do have only one answer. In case they have more than one then the question is cancelled. The universities sometimes provide the answer to all questions after the exam. The correct answer was given in the booklet, and I added it here in order to help anyone who tries to solve the question.