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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi bobbym,

The solution #1674 is correct. Neat work!

#1675. Find the sum of all natural numbers less than 200 which are divisible by 5.

**The divergent series are the invention of the devil, and its a shame to base on them any demonstration whatsoever - Neils Henrik Abel**.**Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it - Samuel Johnson.**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi bobbym,

The solution #1675 is perfect. Good work!

#1676. Find the sum of all the natural numbers between 200 and 300 which are divisible by 4.

**The divergent series are the invention of the devil, and its a shame to base on them any demonstration whatsoever - Neils Henrik Abel**.**Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it - Samuel Johnson.**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi bobbym,

The solution #1676 is perfect. Neat work!

#1677. Find the Arithmetic Progression whose sum to n terms is 2n[sup]2[/sup] + 2. (Find the values of the AP)

**The divergent series are the invention of the devil, and its a shame to base on them any demonstration whatsoever - Neils Henrik Abel**.**Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it - Samuel Johnson.**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi bobbym,

#1678. The houses of a row are numbered consecutively from 1 to 49. Show that there is a value of x such that the sum of the numbers of the houses preceding the house numbered x is equal to the sum of the numbers of the following it. Find this value of x.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi bobbym,

The solution #1678 is correct. Marvelous!

#1679. Find a[sub]30[/sub] - a[sub]20[/sub] for the Arithmetic Progression : a, a + d, a + 2d, a + 3d, ......

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi bobbym,

The solution #1679 is correct. Good work!

#1680. Two Arithmetic Progressions have the same common difference. The difference between their 100th term is 111222333. What is the difference between their millionth terms?

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,954

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

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi anonimnystefy and bobbym,

The solution #1680 is correct. Well done!

#1681. Which term of the Arithmetic Progression 21, 18, 15, ..... is 0?

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,954

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

The knowledge of some things as a function of age is a delta function.

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi bobbym and anonimnystefy,

The solution #1681 is correct. Neat work!

#1682. Find the 30th term of the Arithmetic Progression 10, 7, 4, ......

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi bobbym,

The solution #1682 is correct. Neat work!

#1683. If a = -18, n = 10, a[sub]n[/sub] = 0, find d.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

Offline

**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 15,954

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

The knowledge of some things as a function of age is a delta function.

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi bobbym and anonimnystefy,

The solution #1683 is perfect. Neat job!

#1684. If a = 3.5, d = 0, n = 105, find a[sub]n[/sub].

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 98,295

Hi;

**In mathematics, you don't understand things. You just get used to them.**

**If it ain't broke, fix it until it is.** **Thinking is cheating.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 18,127

Hi bobbym,

The solution #1684 is correct. Good work!

#1685. Find the number of odd numbers between 0 and 50.

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