# One of These Things is Not Like the Others

1. Nov 6, 2009

### Quixotic

Struggling with this one. What do you think?

Which of the five figures does not share the same basic, common feature that the others share?

http://img12.imageshack.us/img12/7317/spatial1.png [Broken]

The figures aren't perfectly recreated in the image - assume that the shape in the middle is a perfect square and is centered inside another perfect square.

EDIT: image fixed. Terribly sorry for the goof.

Also, if this stimulates interest, I've got another I can post.

Last edited by a moderator: May 4, 2017
2. Nov 6, 2009

### Jonathan Scott

I think the feature is ...
symmetry

3. Nov 6, 2009

### Quixotic

Meaning they're all asymmetric except for B?

4. Nov 6, 2009

### DaveC426913

No.
B is rotationally symmetric. They're all symmetric except D.

5. Nov 6, 2009

### Quixotic

I'm not seeing the symmetry in A, C, and E. 2 dimensional or 3?

6. Nov 6, 2009

### DaveC426913

??
They're all mirror symmetry about an axis.

7. Nov 6, 2009

### Quixotic

Brain fart, nevermind. I see it.

8. Nov 6, 2009

### DaveC426913

D has no symmetry. Look again. Your brain seems to have gas

9. Nov 6, 2009

### Quixotic

This is embarrassing... I made a mistake with my image. The bottom half of D should look like the top half. I wasn't looking at my own image, I was looking at the original image in print.

10. Nov 6, 2009

### BobG

B is the only item that has lines that don't border a square (assuming overlapping squares). A, C, and E are obvious; D takes a tiny bit of diligence.

11. Nov 6, 2009

### Jonathan Scott

OK, in that case the feature is ...
mirror symmetry, and B is the odd one out

12. Nov 6, 2009

### Quixotic

The second set of figures:

http://img11.imageshack.us/img11/3806/spatial2.png [Broken]

Same instructions.

Last edited by a moderator: May 4, 2017
13. Nov 6, 2009

### DaveC426913

B is the only one that cannot be drawn in its entirety with a single, unbroken line.

There is a quick trick to this. Some intersections contain an odd number of spokes. Ergo: endpoints of more than one line.

14. Nov 6, 2009

### Quixotic

My first guess too, but we're looking for a basic, common feature, and what's even simpler is that

all the figures except C feature triangles.

Or is that too simple?

15. Nov 6, 2009

### DaveC426913

Personally I think my answer is more elegant. I think the answer you gave is too ... trivial.

You could go even simpler and say c is the only one with no diagonal lines.

16. Nov 6, 2009

### Quixotic

Personally I think yours is more elegant also.

17. Nov 6, 2009

### Soca fo so

I like Dave's answer, but also couldn't an alternative answer be D following the same reasoning as for the first question?