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Numerical Series

Numerical Series

Numerical Series

(OP)
Which number comes next: We've all seen these series questions in different types of tests, like

1, 1, 2, 3, 5, 8, 13, ...
2, 4, 8, 16, ...

Here's a tricky one that I came across - Give the next number in the series

8, 5, 4, 9, 1, 7, ..

Let's wait a week to post answers so as not to reveal the secret.

Larry

RE: Numerical Series

try this one....


8,6,7,5,3,0,?

RE: Numerical Series

Jenny Jenny who can I turn to?

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"It's the questions that drive us"
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

RE: Numerical Series

how about 9, 6, 3, 2, 1, 4, ...

RE: Numerical Series

These number series problems always bothered me.  The problem isn't that I can't figure out the next number in a logical series.  Quite the opposite.  The problem is that most of these problems have multiple answers that can be given that will be logically correct.  Most of the series aren't constrained tightly enough.  I've taken entrance exams and IQ tests that have multiple choice answers to these questions, and several of the answers can be made to fit logically.  It's agitatin', you know?

RE: Numerical Series

8, 5, 4, 9, 1, 7...    6, 3, 2, 0

How do I get my prize?  ;)

For those that want to know the pattern, it is not like the examples that TangoCleveland provided. It is not like the Fibonacci sequence, or a geometric series, because it isn't an infinite sequence.  The pattern stops at zero.

RE: Numerical Series

Oops!  Sorry TC, I forgot you wanted the solution kept quiet.

Well, I didn't come right out and say it, anyway.

RE: Numerical Series

(OP)
DReimer,
Right, but I'm glad you didn't say why.  I'm still puzzling out the other offerings...

Larry

RE: Numerical Series

Here's a "non-numerical" sequence to consider:

O, T, T, F, F, S, .....

RE: Numerical Series

I agree with Eltron.  Depending on the interpretation of the sequence's underlying generator, you can get different results - and it is agitating. Then again, trying to find all different answeres to the origianl sequence is kind of fun.

RE: Numerical Series

how about 1,5,8,11,15,14,17 ...
or 2,9,3,12,19,13,21 ...

RE: Numerical Series

DReimer,
If you think about it it is infinite. (78, 654, 31, 27...)

RE: Numerical Series

I would love to see that one on an IQ test Hoagie.

Probably get yelled at though for being 'ethnocentric' or something...

RE: Numerical Series

"O, T, T, F, F, S, ....."

S, E, N, T, E, T, T, F, F, S, S, E, N, T.....

Maybe I'd seen this one before, but it just popped into my head. Scary.

Rerig

RE: Numerical Series

This thread is an interesting study in human nature, and mimics what I have seen in other fora when trivia or other questions are posed.  Instead of offering an answer to the question, many contributors pose other questions.

There must be a phenomenon at work here...  I wonder if anyone has studied it?

RE: Numerical Series

Well, I've just made one up, let's see if anyone gets it

1 4 9 6 5 6 9

To be honest I just find these things just annoying, arbitrary puzzles that you can only get if you think like the puzzle setter.



Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: Numerical Series

greg - 1 4 9 6 5 6 9... 4, 1, 0, 1 4 9 6 5 6 9... 4

mine was made-up too.  Don't need to anything more about me than that I was sitting at a typical keyboard when I typed it in (9 6 3 2 1 4... 7 8 5).

RE: Numerical Series

12 1112 3112 132112 ?

RE: Numerical Series

Ah, there should be a 2 in front of that one Tomfh, and strictly speaking that breaks the sequence.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: Numerical Series

My particular sequence begins with '12'. The first term is arbitrary in these things. The rule is what counts.

RE: Numerical Series

Which is precisely why I don't really enjoy these things -- if they are subject to arbitrary rules then anything goes.

1113122112 btw

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: Numerical Series

How about:

3 3 5 4 4 3 5 5 4 3 ...

It's an infinite series, but the numbers remain surprisingly small.

RE: Numerical Series

Julian:

The numbers do get bigger - and hyphenated!
   
 You'll have no trouble with 7 8 5 5 3 4 4 6 9 .....  

RE: Numerical Series

(OP)
Back to the first post, in case you haven't guessed, it's the numbers in alphabetical order in English.

Larry

RE: Numerical Series

Tango - I didn't spot that - doh.

Strictly speaking, it's the English names of digits, not numbers.

8, 800, 808, 888, 885 ....... gets a bit tedious

RE: Numerical Series

So it wasn't a numerical problem at all. Hence my grizzlement.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: Numerical Series

(OP)
A series is a series, whether it's numerical or not.  They're all just pattern recognition.  An original series can be a building block for a meta-series - that's how musical compositions are written.  Take a motif, and expand it using some rules and conventions, break some of the rules, add some variations, and you have a symphony....

Larry

RE: Numerical Series

Well, jeez. Look at the thread title. Anyway, you could argue that if you aren't going to treat numbers as numbers then the following is valid:

1 2 3 4 5 6 7  _  _

answer 9 8, as I have decided that for the purposes of this puzzle 8 means 9 and 9 means 8



Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: Numerical Series

GregLocock,

You are absolutely right - these puzzles can be quiet arbitrary and infuriating. How about:

! @ # % * !# @!

It's a numerical series (not a string of obscenities), but to make it "interesting", I have substituted the conventional symbols for numerals with my own symbols. First, you have to work out my code, and THEN you have to work out my numerical series.

(Or, you can work out my series first, and then work out my code, if you prefer!)

RE: Numerical Series

Or we can ignore it completely & do something useful instead. smile

cheers
Helpful SW websites  FAQ559-520
How to get answers to your SW questions  FAQ559-1091

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