# Ask for suggestion on a hard IQ question

I joined the IQ test online, and got stuck on this question. Unfortunately, they just gave me the total score, not the answer on every individual question. So I still have no idea how to solve it or the answer. If any one can give me a hint, I really appreciate it. Thanks

(Here is the url for the test https://www.iq-test.net/free-iq-test.html, question is number 24)

I'd say:

B (WBB).

Because:

We have three black squares. They all move each turn, but according to different rules. Block A starts in position 3 and goes left 1 each turn (3,2,1,6,5). Block B starts in position 4 and goes left 1 each turn (4,3,2,1,6). Block C then goes 5,5,6,2,5, as it goes right +0, +1, +2, +3. Blocks A and C now occupy the same position.

• I think it's the only reasonable explanation for this problem. Thanks a lot – le duc quang Sep 30 '18 at 15:12

I would choose

Because

I found two patterns which ended up in this configuration. The simplest one is:

Label the dark squares 1, 2, 3. Then 1 always moves left one square, 2 always moves left one square and 3 moves right 0, then 1, then 2, then 3 squares.
This is shown in the following:

It doesn't feel like this is the only possible pattern, but perhaps it is the only one that fits one of the possible solutions.

• Yeah, it sounds correct and rational. Thanks for your answer – le duc quang Sep 30 '18 at 15:12

I'd say that

As we see in in rows No. 1-4, there are

Always 3 white squares and 3 black squares

The pattern from row No. 1 to row No. 2 is that

2 black squares go to the left

While

The remaining 1 black square goes to the right

This pattern also applies from row No. 2 to row No. 3, but from row No. 3 to row No. 4,

The black squares don't move at all

This means that

The black squares are not supposed to move further as they are all at the end

As such,

The pattern in row No. 4 should be the same as in row No. 5
This means that there is no correct answer

Another thing that I noticed is that

The number of black squares are either 1 or 2 while the pattern in rows No. 1-4 all have 3 black squares.

• $(+1)$ for a unique suggestion :P – Mr Pie Oct 3 '18 at 5:03