Mensa Finland IQ Test Puzzle 34 - big and small squares on a line

Today I was going through the Mensa Finland IQ test and I came across this puzzle:

After finishing the test the first time i came back to the question and struggled to find a logical way to solve it. 30 minutes later i decided to test which answer was correct. I figured that knowing the answer would lead me to having an easy way to find the pattern but i still couldn't find it.

I'm very curious if anyone at all can find the logical pattern in this puzzle or if there is even a logical pattern to find in this puzzle.

I have a strong suspicion that it's actually a puzzle without an answer and the answer is just randomly picked from time period to time period.

Spoilers if you don't want to know the "answer":

Answer number 5 (bottom middle answer) gave me +3 IQ when i answer it instead of other answers, therefore i thought it was the real answer. I found a 2 year old post about the same question from the old "Mensa Norway IQ Test": Mensa online IQ test question - big and small squares on a horizontal line Picture:

* Mensa question - groups of three white, shaded, black squares
* Mensa Norway 2019 questions 8, 12, 17, 18, 31

Is this puzzle unsolvable? Or am I just mistaken?

Adding the left and middle square gives the "right" answer in the right square. The rules that are key here are:

1.) Two small squares being "added" gives a bigger square 2.) Adding anything to a bigger square does nothing 3.) Going column-wise from top to bottom, adding the top and middle picture ALSO has the effect of changing the orientation of the squares.

With these rules in mind, its easy to see that the final result is 2 large squares and two smaller squares facing downwards. However in the old test the closest answer to this is 5. This is either Mensa's fault for accidentally reflecting the image or done on purpose to try and throw off a participant from the consistent rules being followed. Nevertheless, the correct answer can be reached by following this algorithm

Do you want to understand why 5 is the answer? I am sure you figured it out, but just to be clear

it seems that you add up the left and the centre picture of each row to make the right hand picutre, which is why 5 is correct.

Why the correct answer is not available in the test you took I don't know, but I expect it is just simply an error in the MENSA question. I would not 'overthink it' - to me the simplest explanation is that there is a mistake.

• Yes, I agree it would easily be answer #5 in the old version of the test but then again people commented on another post about the old version and claimed that answer 3 gave them a higher score than answer 5. Also I thought Mensa was big enough in the IQ test world that they wouldn't make a simple mistake like that. Just really bothers me that i can't know if its a problem with the IQ test itself or if i'm just not able to see the solution. May 4, 2020 at 2:15
• But then again Puzzle 31 from Mensa Norway is kind of similar and there is no way that Mensa would make the same mistake twice? May 4, 2020 at 2:16

I would say that 'A' seems a reasonable answer in the second version. Addition is performed across rows/columns, using base 3 representation, so that a large square is equal to three smaller squares.