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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

**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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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
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Good!

Example:

T[sub]4[/sub] means that you need to get the 5th triangular number because T[sub]0[/sub] is 1, the first triangular number.

Okay!

Next question:

Numbers 3 4 5

Operations T +

Answer 46

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

Hi;

The first triangular number is 0, so T0 = 0.

But using your definition we can say

T3 + T4 + T5 = 46

**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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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
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Oh. My classmate taught me that T thing.

Number 14 28 42

Operation + - [sup]2[/sup]

Answer 1764

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

42^2 = 1764

**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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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
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New edition :

P * C.P = 5

P = Prime

C = Composite

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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it can't be.

5 = 5*1 and there isn't any other factorisation

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'Humanity is still kept intact. It remains within.' -Alokananda

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

Hi julianthemath;

5 only has the factorization of 5 x 1. 1 is not composite or prime. Please post another problem this one has no solution.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
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C.P means decimal number. Try again.

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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**mathdad****Member**- Registered: 2013-04-13
- Posts: 21

julianthemath wrote:

New edition :

P * C.P = 5

P = Prime

C = Composite

Still not possible.

All P are such that P > 1. The smallest P is 2. And, the smallest C such that C > 0 is 4

Thus P * C.P >= 2 * 4.d = 8.0 + 2d (where 2d is 2 times the decimal part)

If you were trying to go for 2 * 2.5, then the 2 in 2.5 is not Composite, it is Prime.

*Last edited by mathdad (2013-04-22 09:04:17)*

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
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Oh, well.

No answers, no points.

Wanna ask, mathdad? bobbym? Or just keep me?

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

Hi;

Okay, let me see the answer. Please hide the answer cause someone else may still want to work on it.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
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81 + X - 4 = 85

Solve for X.

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

Hi;

Thanks for the answer.

X = 0

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
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Again!

81 + X - 4 = 85

You might have an error.

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

H;

81 + X - 4 = 85

Add 4 to both sides:

81 + X = 89

Subtract 81 from both sides.

X = 8

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
- Website

Wow.

1777 - 777 + 777 * 777 = ?

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

604729 is the answer.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
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Wow!

This time, there are points.

X + X = X

What makes this impossible to answer? 30 points

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

Nothing, X can be 0.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
- Website

Oh. How do you like my signature? Funny, right?

Bobbym - 30

3 6 9 15 ? What is the fifth number?

*Last edited by julianthemath (2013-04-25 21:01:50)*

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

I like 21 as the nest number.

I worked a long time on bobbym - 30 but could not come up with anything.

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
- Website

Oh.

Bobbym - 60

If China has a population of 1,234,567,890,

India 123,456,789

USA 12,345,678

Indonesia 1,234,567

What is the population of Brazil?

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,676

Is it 123 456 ?

How are the chickenpox?

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

Combinatorics is Algebra and Algebra is Combinatorics.

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
- Website

No. I didn't have it, my cousins do. The start of the infection was during the afternoon I came home after my last exams. And now, some of my cousins are having the chickenpox. So, I just need to stay inside.

Yes. It is 123,456.

Bobbym - 90

If Gangnam style were a country (by no. of views), what rank is it?

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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