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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

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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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

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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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

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.**

**Online**

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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

**igloo** **myrtilles** **fourmis**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

Hi;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,522

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

Hi;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

**Online**

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

Hi ganesh;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

Hi ganesh;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

**Online**

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

Hi ganesh;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

**Online**

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

Hi;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

**Online**

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

Hi ganesh;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

**Online**

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,365

Hi ganesh;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

**Online**

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,403

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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