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#2326 2012-12-03 18:41:59

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi bobbym,

The solution #1662 is correct. Good work!

#1663. Which term of the Arithmetic Progression 3, 8, 13, 18 ..... is 78?


Character is who you are when no one is looking.

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#2327 2012-12-03 20:13:15

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi;


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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#2328 2012-12-04 18:19:42

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi bobbym,

#1664. If the 3rd and the 9th terms of an Arithmetic Progression are 4 and -8 respectively, which term of this Arithmetic Progression is zero?


Character is who you are when no one is looking.

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#2329 2012-12-04 18:26:32

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi;


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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#2330 2012-12-05 19:02:22

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi bobbym,

The solution #1664 is correct. Neat work!

#1665. Two APs have the same common differences. The difference between their 100th terms is 100, what is the difference between their 1000th terms?


Character is who you are when no one is looking.

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#2331 2012-12-05 20:48:29

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi;


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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#2332 2012-12-06 18:46:15

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi bobbym,

The solution #1665 is perfect. Neat work!

#1666. For what value of n, are the nth terms of two Arithmetic Progression : 63, 65, 67, .... and 3, 10, 17, .... equal?


Character is who you are when no one is looking.

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#2333 2012-12-06 19:16:30

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,562

Re: Oral puzzles


igloo myrtilles fourmis

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#2334 2012-12-06 21:51:05

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi;


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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#2335 2012-12-07 19:13:07

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi John E. Franklin and bobbym,

The solution #1666 is perfect. Neat job!

#1667. Determine the Arithmetic Progression whose third term is 16 and the 7th term exceeds the 5th term by 12.


Character is who you are when no one is looking.

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#2336 2012-12-07 19:19:50

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,507

Re: Oral puzzles

Hi ganesh


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#2337 2012-12-07 21:14:36

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi;


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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#2338 2012-12-08 19:31:11

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi anonimnystefy and bobbym,

The solution #1667 is correct. Good work!

#1668. Find the sum of the following Arithmetic Progression : 0.6, 1.7, 2.8,   to 100 terms.


Character is who you are when no one is looking.

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#2339 2012-12-08 20:58:27

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi ganesh;


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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#2340 2012-12-09 19:04:41

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi bobbym,

The solution #1668 is perfect. Fabulous!

#1669. Find the sum of the Arithmetic Progression to 11 terms : 1/15, 1/12, 1/10, ......


Character is who you are when no one is looking.

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#2341 2012-12-09 21:29:59

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi ganesh;


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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#2342 2012-12-10 19:37:37

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi bobbym,

The solution #1669 is correct. Marvelous!

#1670. In an Arithmetic Progression, given a = 7, a[sub]13[/sub] = 35, find d and S[sub]13[/sub].


Character is who you are when no one is looking.

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#2343 2012-12-10 19:44:21

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi ganesh;


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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#2344 2012-12-11 18:22:24

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi bobbym,

The solution #1670 is correct. Good work!

#1671. In an Arithmetic Progression, given d = 5, S[sub]9[/sub] = 75, find a and a[sub]9[/sub].


Character is who you are when no one is looking.

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#2345 2012-12-11 20:44:41

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi;


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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#2346 2012-12-12 18:59:20

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi bobbym,

The solution #1671

#1672. The first and the last terms of an Arithmetic Progression are 17 and 350 respectively. If the common difference is 9, how many terms are there and what is their sum?


Character is who you are when no one is looking.

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#2347 2012-12-12 19:28:28

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi ganesh;


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.

Offline

#2348 2012-12-13 17:54:43

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi bobbym,

The solution #1672 is correct. Brilliant!

#1673. If the sum of first 7 terms of an Arithmetic Progression is 49 and that of 17 terms is 289, find the sum of first n terms.


Character is who you are when no one is looking.

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#2349 2012-12-13 20:53:27

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 85,265

Re: Oral puzzles

Hi ganesh;


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.

Offline

#2350 2012-12-14 21:56:27

ganesh
Moderator
Registered: 2005-06-28
Posts: 13,849

Re: Oral puzzles

Hi bobbym,

The solution #1673 is perfect. Good work!

#1674. Find the sum of the odd numbers between 0 and 50.


Character is who you are when no one is looking.

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