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#1 2012-05-27 17:58:11

whatthe
Member
Registered: 2012-05-27
Posts: 6

Number Patterns??

Ive been asked to solve the following:

1,4,16,25,....,....,....any tips on the next 3 numbers.
Ive come up with 49,64,100
I could understand if there was a 9 between the 1 & 4 but it wasnt in the question.

mad

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#2 2012-05-27 18:17:51

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: Number Patterns??

Hi;

Welcome to the forum. I am getting that too.


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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#3 2012-05-27 19:01:17

bob bundy
Moderator
Registered: 2010-06-20
Posts: 6,376

Re: Number Patterns??

hi whatthe

Welcome to the fourm!

Me too.  You could probably make up a rule to allow for that like:

The square numbers leaving out every third square, which seems to be your idea, but four instances are not enough to establish that rule properly.

The square numbers leaving out any square with a 9 in it would give 1,4,16,25,36,64,81, ...

I wonder if there's any clue in the source?

Where did you get it from?

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#4 2012-11-26 19:44:48

whatthe
Member
Registered: 2012-05-27
Posts: 6

Re: Number Patterns??

An aptitude test for yr 10 students, got it from a TAFE Teacher.

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#5 2012-11-26 20:15:15

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: Number Patterns??

Hi whatthe;

Those aptitude tests where people guess a pattern are mathematically incorrect in the sense that there are an infinite number of patterns ( equations ) from the same set of data. Each one just as valid as any other.


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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#6 2012-11-27 10:13:42

noelevans
Member
Registered: 2012-07-20
Posts: 236

Re: Number Patterns??

Amen to that bobbym! smile

I hate such questions.  It just shows the ignorance of the test writers.  The sequence could have
been 1,4,16,25,1,4,16,25,1,4,16,25...  or 1,4,16,25,pi,1,4,16,25,pi...  or  any repeating sequence
that begins with 1,4,16,25 among other possibilities like 1,4,16,25,28,30,39,... where one keeps
adding 3 then 12 then 9 repeatedly. 

Also those tests that have 3 (usually) pictures and the test taker is supposed to figure out the fouth
picture (from a list of 4 or more given pictures) are faulty.  Those that don't think the same way
that the test maker does have their answers counted wrong although they may have just as valid
a reason for their choice.

Some of the questions on those tests sometimes show a lack of understanding of the test taker's
creativity and intelligence.

I saw a test once that was testing quality control.  Out of 100 questions 10 of them were messed
up one way or another.  One of the questions was:

    A stock was purchased for $100.  At the end of the 1st month it had lost 50% of its value.  In
the next month it gained 50% of the value it had at the end of the 1st month.  How much was
the stock worth at the end of the 2nd month?
Choices
a)  $100
b)  $75
c)  $50
d)  It's hard to understand the stock market.
e)  $200
Their "correct answer" was b AND d.

Go figure!  How can one pass a test with such questions?
It's easy to understand the stock market:  people buy and sell stocks.
PREDICTING what the stock market is another matter.


Writing "pretty" math (two dimensional) is easier to read and grasp than LaTex (one dimensional).
LaTex is like painting on many strips of paper and then stacking them to see what picture they make.

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#7 2012-11-27 10:27:28

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,228

Re: Number Patterns??

Those that don't think the same way
that the test maker does have their answers counted wrong

Yep!

Find the next term 1, 2, 4,...

Answer 8, brilliant! The interrogator is happy. But what about the simpler answer of 7?


In mathematics, you don't understand things. You just get used to them.
Of course that result can be rigorously obtained, but who cares?
Combinatorics is Algebra and Algebra is Combinatorics.

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#8 2012-11-27 20:25:29

bob bundy
Moderator
Registered: 2010-06-20
Posts: 6,376

Re: Number Patterns??

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#9 2012-11-28 14:07:00

noelevans
Member
Registered: 2012-07-20
Posts: 236

Re: Number Patterns??

Or maybe the next for 1,2,4 considering it as a list of consecutive positive integers whose spelling is less than five letters long:
1, 2, 4, 5, 6, 9, 10 --- a FINITE sequence.  smile


Writing "pretty" math (two dimensional) is easier to read and grasp than LaTex (one dimensional).
LaTex is like painting on many strips of paper and then stacking them to see what picture they make.

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#10 2012-11-28 18:20:28

Calligar
Member
Registered: 2011-09-24
Posts: 234

Re: Number Patterns??

Hi whatthe!

Welcome to the forum!


Life isn’t a simple Math: there are always other variables.  -[unknown]

But Nature flies from the infinite, for the infinite is unending or imperfect, and Nature ever seeks an end.  -Aristotle

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