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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,428

Hi bobbym,

The solutions #4488 and #4489 are correct. Superlative!

#4490. Find k, if the given value is the kth term of the given Arithmetic Progression : -1, -3, -5, -7 ...... x = -151.

#4491. Find a[sub]30[/sub] - a[sub]20[/sub] for the Arithmetic Progression : -9, -14, -19, -24, ........

Character is who you are when no one is looking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,493

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: 14,428

Hi bobbym,

The solutions #4490 and #4491 are correct. Neat work!

#4492. Two Arithmetic Progressions have the same common difference. The first term of one of these is 3, and that of the other is 8. What is the difference between their 2nd terms?

#4493. Two A.P.s have the same common difference. The first term of one of these is -1, and that of the other is -3. What is difference between their second term?

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: 86,493

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: 14,428

Hi anonimnystefy and bobbym,

The solutions #4492 and #4493 are correct. Well done!

#4494. Find the sum : 2 + 4 + 6 + ....... + 200.

#4495. nth term of a sequence is a + nb. Find a[sub]4[/sub] - a[sub]3[/sub].

Character is who you are when no one is looking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,493

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**

**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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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 14,428

Hi bobbym and anonimnystefy,

The solutions #4494 and #4495 are correct. Neat job!

#4496. How many two-digit numbers are divisible by 3?

#4497. Find the 11th term from the last term of the Arithmetic Progression : 10, 7, 4, ........, -62.

Character is who you are when no one is looking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,493

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: 14,428

Hi bobbym,

The solution #4496 is correct. Good work!

The solution #4497

#4498. For what value of n, are the nth terms of two Arithmetic Progressions : 63, 65, 67, .... and 3, 10, 17, .... equal?

#4499. If a = 7, d = 3, n = 8, find a[sub]n[/sub].

Character is who you are when no one is looking.

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
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"Double the fun, double the thrill, double the coolness" - Julianthewiki

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

Hi ganesh

*Last edited by anonimnystefy (2012-12-22 23:17:22)*

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: 86,493

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: 14,428

Hi,

The solutions #4496 and #4497 are

, julianthemath.The solutions #4498 and #4499 are correct. Excellent, anonimnystefy and bobbym!

#4500. If d = -3, n = 18, a[sub]n[/sub] = -5, find a.

#4501. If a = -18.9, d = 2.5, a[sub]n[/sub] = 3.6, find n.

Character is who you are when no one is looking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,493

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: 14,428

Hi bobbym,

The solutions #4500 and #4501 are correct. Neat job!

#4502. If 6 times the 6th term of an Arithmetic Progression is equal 7 times the 7th term, then what is the 13th term of the A.P.?

#4503. If pth, qth, and rth terms of an Arithmetic Progression are a, b, c respectively, then a(q-r) + b(r-p) + c(p-q) = ?

Character is who you are when no one is looking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,493

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: 14,428

Hi bobbym,

The solutions #4502 and #4503 are correct. Neat work!

#4504. In an Arithmetic Progression, if l = 28, S = 144, n = 9, find a.

#4505. In an Arithmetic Progression, if a = 3, n = 8, S = 192, find d.

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.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,493

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: 14,428

Hi anonimnystefy and bobbym,

The solutions #4504 and #4505

In triangle ABC, right angled at B, AB = 24 cm, BC = 7 cm. Determine:

#4506. sin A, cos A.

#4507. sin C, cos C.

Character is who you are when no one is looking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,493

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: 14,428

Hi bobbym,

The solutions #4506 and #4507 are correct. Good work!

If sin A = 3/4, calculate

#4508. cos A

#4509. tan A.

Character is who you are when no one is looking.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,493

Hi;

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

Combinatorics is Algebra and Algebra is Combinatorics.

**Online**