# Which is the odd one out and why?

This question is about finding the odd one. My question is what is the answer and what is the reason behind it. Also, how should we approach such questions.

Puzzle 1 Puzzle 3 • Generally the asker is supposed to accept the answer which has answered his question by clicking on the tick next to the votes. – Beastly Gerbil Mar 24 '16 at 14:49

Puzzle 1:

The third is the odd one out. All three arrows curve the same way in this image whereas they curve different directions on 1, 2 and 4. Also, the top arrow curves towards the other arrows but in 1, 2 and 4 the top arrow curves away from the others.

Puzzle 2 and 3:

The reason is the same in these two puzzles. In puzzle 2 it is the second image which is different and in puzzle 3 it is the fourth image. The reason is that the odd-image out is a rotation plus mirror transformation whereas the other three are just rotations.

• This is the same answer I came but I would add puzzle 1 can be considered a rotation too. – LinkBerest - Goodbye SE Jan 27 '16 at 3:34
• @JGreenwell yes that is a good point. The top arrow is mirrored about its own longitudinal axis, which means if you ignore the two below arrows, then puzzle 1 shares the same set of transformations (with different rotation values) as 2 & 3. – jhabbott Jan 27 '16 at 3:47
• yep, I thought that switch in rotation values (given the name) was the OP trying to throw guessers off – LinkBerest - Goodbye SE Jan 27 '16 at 3:51
• I don't get why you give different reasoning for Puzzle 1, and for Puzzle 2-3. It's all the same reasoning. (keeping this spoiler free) - @thepace 's answer somewhat correctly gives the global reason for each puzzle. But basically, the exact same rule gives you the odd one out for each puzzle. The rule does not differ from one puzzle to the next. – Spacemonkey Jan 27 '16 at 19:39
• @Spacemonkey The reason for two different explanations, is that in puzzle 2 and 3 the odd one out is a direct mirror image of the other three images (plus rotation), whereas in puzzle 1, the odd one out is not an exact mirror image. If you split the three arrows up into separate components, only one of them is mirrored, the other two are not mirrored, therefore the image as a whole is not an exact mirror image of the other three. – jhabbott Mar 12 '17 at 17:26

Puzzle 1:

The third one, as it is the only one where all the arrows face the same way, the others the one on top faces a different direction from the rest

Puzzle 2:

The second, the flower is on the left of the stem

Puzzle 3:

The fourth, the spiral goes left out from the centre

Nice Puzzle!

To do this, I look for a common link and see if there is a picture without the link

• Puzzle 2 - In the first, the flower is at the bottom and not at the left. – dexterous Jan 27 '16 at 2:20
• @dexterous_stranger When you rotate the first flower by 180 degrees, the flower is on the left. Basically, all three sets of puzzles are just the same figure rotated to make it look different. The odd ones out are those that are different from the original rotated image. – Takeshi Jan 27 '16 at 3:55
• @dexterous_stranger He is saying that these ones are mirrored differently to the other images of each set, thats immediately what I noticed too. – Daedric Jan 27 '16 at 14:23
• People.... rotation != mirroring . We don't care about mirroring here. All correct images are rotations of one another. Anything that isn't rotated is the odd one out. as simple as that. To JoeBeastlyGerbil, you are kind of missing what was the common link you looked for... – Spacemonkey Jan 27 '16 at 19:42

Just to add to the "Also, how should we approach such questions" part of your question, my first instinct upon seeing the puzzle was to notice that all four circles in each set appeared to be rotations of each other. Because the question asked for the 'odd one out', that gave me a hint that perhaps one of the circles, despite appearing to be the same as the others, was not the same. It then became a simple exercise of identifying which one was different.

• How about the flower one? – dexterous Jan 27 '16 at 2:23
• @dexterous_stranger the flower one is just like the other two puzzles. 3 of the flowers are identical and 1 of them is different (or more specifically, a mirror image of the others) – AZGreenTea Jan 27 '16 at 5:11

Puzzle 1:

3rd picture. All the rest can be seen as a clockwise rotation of the other images. The 3rd one doesn't. Also it has three arrows in same pattern

Puzzle 2:

2nd picture. All the rest can be seen as a clockwise rotation of the other images. The 2nd one is a mirror image of one of the rotations.

Puzzle 3:

4th picture. All the rest can be seen as a clockwise rotation of the other images. The 4th one is a mirror image of one of the rotations.

Reason:

Rotating an image in clockwise direction brings the other three images. While the odd one is a mirror of one of the clockwise rotated images.