# One hard IQ question

Can someone explain me the logic behind this?

The question is: What comes next in the pattern (out of the 5 possibilities)

• Hard is subjective. – Insane Jun 5 '16 at 4:36
• The idea is to cyclically left-rotate the sequence, moving the first place tile to the last place, by continually swapping it with its right neighbor. After it reaches last place (by 2 swaps), rotate the sequence again, moving the new first tile to last place, etc. This is a standard method to cyclically shift. – Bill Dubuque Jun 6 '16 at 0:18
• Like @Insane said, hard is subjective. Probably what caught people out was that the slash symbols stay at the edges for 2 times before moving the the other side. – Bradman175 Jun 6 '16 at 8:42
• I got E right away but cannot really articulate why, so that's why I didn't answer (and there's 10 already). I see it as basic pattern recognition which I picked up right away. – Insane Jun 6 '16 at 9:00

As far as I can tell, the answer is

E

Because:

The pattern is alternatively swapping the leftmost two tiles and the rightmost two tiles:

To get the sixth configuration, we need to swap the leftmost two tiles again:

Additionally, the sequence cycles after this, so if we swap the rightmost two tiles again, we end up at the starting configuration:

I liked this IQ puzzle, because I was stuck on thinking the tiles were inverted in some steps for a while, leading me on a search for complicated patterns, while it was a fairly simple pattern after all. Nice trick question :P

E

Explanation:

Think of the two parts as two tiles like in a shuffle puzzle, then the pattern goes flip slide slide, flip slide slide. The GIF below (made by @Decent Dabbler) demonstrates the cycle.

Huge shout out and thank you to @Decent Dabbler for making the GIF for me.

• Do i have to slide the tiles to the right everytime? Sliding right on the 5th picture should start again at left side i presume? Then i come to the solution A – Ozkan Jun 4 '16 at 8:49
• Edit: I'm sorry my bad. I gathered two separated steps to one. You are right I think – Ozkan Jun 4 '16 at 8:55
• @Ozkan Sorry about the confusion, I'll be sure to create a visual once I have the resources to – Xylius Jun 4 '16 at 9:01
• @Ozkan It seems to just be continually moving to the right. Think of the tiles as being on a grid of squares expanding infinitely in both directions, rather than it being three squares that the tiles loop around on. – Anthony Grist Jun 4 '16 at 12:42
• I've created an animated GIF to illustrate what you mean. If you want, you can add it to your answer. – Decent Dabbler Jun 5 '16 at 12:41

E

because

There are 6 ways to arrange those square shapes. One is missing, which is E

• B is also missing. – Inazuma Jun 4 '16 at 11:58
• @Inazuma It's repeating. – newzad Jun 4 '16 at 12:15
• This is a remarkably elegant answer. @Inazuma: “rearrange” here should be read as “reorder” — no flipping/rotating the tiles, just permuting the order. – Peter LeFanu Lumsdaine Jun 4 '16 at 12:16
• The problem with this answer is that the sequences in IQ-test-questions doesn't work this way. And this is a sequence, since the objects arranged in a row, otherwise good IQ-test creator would arrange them randomly in space. – klm123 Jun 5 '16 at 10:34
• @klm123 Are you serious? Who says that arranging objects in a row always make the arrangement a sequence? And also maybe "good" IQ test creators knows that any arrangement leads to answer $E$. You can try. – newzad Jun 5 '16 at 10:58

Another solution:

We can think of shapes as numbers.
Let's assume that ascending line is 1, descending line is -1 and no line is 0.

Here we go:

• 1 -1 0
-1 1 0
-1 0 1
0 -1 1
0 1 -1

The third column pattern is xx yy zz, so we need -1 to complete it.
The second column pattern is xyz xyz, we need 0 here.
The first column pattern is again xx yy zz, and we need 1 to complete the column.
Thus we get "1 0 -1".

E

• A great out-of-the-box analysis! Thank you – redolent Jun 5 '16 at 19:03

It's:

E

because

That makes the fourth, fifth and sixth pattern equal to the first, second, and third, rotated by 180 degrees.

It's amazing that almost everyone picked the same pattern, but for totally different reasons!

• Many of the reasons only appear to be different; some of them at least are different ways of saying equivalent things, given the constraints on the moves they describe. – Glen_b Jun 5 '16 at 2:21
• The reason is hidden in @newzad's answer. the thing is everyone is finding the different orders in the full set of 6 permutations of 3 objects. – yukashima huksay Sep 6 '17 at 4:31

Yet another possible explanation for the answer being

E

View the tiles individually, and look at how they move. Both tiles can be seen as repeating the same pattern: 1,2,3, 3,2,1

If you continue this pattern, the next configuration is E, then it loops back around to the first picture.

• This is how I got the answer. – The Guy with The Hat Jun 6 '16 at 20:26
• My thoughts as well. – Meni Rosenfeld Jun 6 '16 at 20:28

I think it's:

E

because:

I think the steps from first to second are: turning the whole thing 180 degrees and then moving the blocks one to the left (the block on the left moves around and becomes the block on the right). The steps from second to third are in reverse order, first move the blocks one to the left and then turn the whole thing 180 degrees. Then the steps from third to fourth are the same as from first to second and so on. It's an alternating pattern. If you use the same pattern on the second one as you did one the first one, you would get the first on again.

I got the same answer as all the other responses.

E

I treat the lines as an arrow "aiming" in a direction. In effect, the arrow is spinning in a circle or hexagon. Pattern: up-left, down-left, down, down-right, up-right... up.

It should be:

E, since all the patterns have their inverse except pattern C.

• essentially same answer as @nikamed; – JonMark Perry Jun 4 '16 at 14:48
• You need to define what you mean by inverse. – Hans Jul 12 '18 at 4:04

## protected by AzaJun 5 '16 at 0:41

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