Author |
Topic: Alphabet Categories (Read 456 times) |
|
otter
Junior Member
Gender: 
Posts: 142
|
 |
Alphabet Categories
« on: May 20th, 2003, 8:54pm » |
 Quote  Modify
|
The letters of the english alphabet can be grouped into four distinct categories. The first 13 letters establish the categories:
A M
B C D E K
F G J L
H I
Place the remaining 13 letters in their proper categories and explain your reasoning.
|
|
 IP Logged |
We shall not cease from exploration. And the end of all our exploring will be to arrive where we started
and know the place for the first time.
T.S. Eliot
|
|
|
Leo Broukhis
Senior Riddler
Gender:
Posts: 459
|
|
Re: Alphabet Categories
« Reply #1 on: May 20th, 2003, 10:31pm » |
Quote Modify
|
No, there are 5 categories. The fifth category consists of three letters.
|
| « Last Edit: May 20th, 2003, 10:32pm by Leo Broukhis » |
IP Logged |
|
|
|
Chronos
Full Member
 
Gender:
Posts: 288
|
|
Re: Alphabet Categories
« Reply #2 on: May 20th, 2003, 11:21pm » |
Quote Modify
|
Leonid, I think that he's putting those in category 3 (with F, G, J, L, and P)
|
|
IP Logged |
|
|
|
redPEPPER
Full Member
Posts: 160
|
|
Re: Alphabet Categories
« Reply #3 on: May 21st, 2003, 2:28pm » |
Quote Modify
|
NSZ
|
|
IP Logged |
|
|
|
Icarus
wu::riddles Moderator
Uberpuzzler
Boldly going where even angels fear to tread.
Gender:
Posts: 4863
|
|
Re: Alphabet Categories
« Reply #4 on: May 21st, 2003, 3:30pm » |
Quote Modify
|
I first saw this one (with the groups all completely specified - your job was only to explain them) in Marilyn Vos Savant's column. She too included NSZ in "group three". I was disappointed to read her explanation that this group consisted of letters "with no symmetry at all!". I agree with Leonid that these three belong in their own category.
|
|
IP Logged |
"Pi goes on and on and on ...
And e is just as cursed.
I wonder: Which is larger
When their digits are reversed? " - Anonymous
|
|
|
otter
Junior Member
Gender:
Posts: 142
|
|
Re: Alphabet Categories
« Reply #5 on: May 21st, 2003, 6:19pm » |
Quote Modify
|
I guess I missed this in Marilyn vos Savant's column. The version I remember had only 4 categories. But the 4 or 5 categories argument nothwithstanding, I see you all have the answer.
|
|
IP Logged |
We shall not cease from exploration. And the end of all our exploring will be to arrive where we started
and know the place for the first time.
T.S. Eliot
|
|
|
Icarus
wu::riddles Moderator
Uberpuzzler
Boldly going where even angels fear to tread.
Gender:
Posts: 4863
|
|
Re: Alphabet Categories
« Reply #6 on: May 22nd, 2003, 3:30pm » |
Quote Modify
|
It was a long time ago, and M.V.S. had only 4 categories too. That was the problem - In her answer to the question, she explained how the other 3 categories were vetically symmetric, horizontally symmetric, and both. Then she asked the readers to identify the property possessed by the fourth category. Her answer at the end of the column was that it consisted of letters with no symmetry at all. Even though it contained N, S, and Z, which are center symmetric. Hence my disappointment.
Actually the puzzle as you stated it has two solutions - in that you can define the 3rd group as "having neither horizontal or vertical symmetry", and the 4th group as "having both symmetries" - in which case NSZ is part of the third group. Or you could define the 3rd group as "not symmetric under rigid transformations" and the 4th group as "symmetric about their centers" - in which case NSZ is part of the 4th group.
|
|
IP Logged |
"Pi goes on and on and on ...
And e is just as cursed.
I wonder: Which is larger
When their digits are reversed? " - Anonymous
|
|
|
|
RIDDLES SITE
WRITE MATH!
Home 
Help 
Search 
Members 
Login 
Register
Reply
Notify of replies
Send Topic
Print