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#1 2010-06-16 21:42:11

Mariner
Member
Registered: 2010-06-16
Posts: 35

Hey, can someone please solve this puzzle?

Last edited by Mariner (2010-06-16 21:54:30)

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#2 2010-06-16 21:51:18

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Hi Mariner;

According to the drawing the first rhombus only has 7 dots or vertices, instead of 8. Is that a mistake or is that what they want?

Going by the drawing:

d4 will have 37 dots. There are 2n-1 rhombuses. 1 rhombus will contribute 7 dots the rest 5, so

dn = 5( 2 ( n -1 ) ) +7

b4 of course is 7. bn = 2n - 1

e4 is 57, at least that is what I am getting. Or 21 depending on your answer about sides! I like 21 so en = 3 *(2n - 1)

p4 = 57 cms. First rhombus contributes 9 edges all the next 8 each. So pn = 9 + 8 ( 2 ( n - 1 ) )

s4 = non perimeter back sides = 21

c4 = 7.

bn = 2n - 1 and cn is the same as bn because there is only one internal dot per rhombus, the one int h back on the bottom, So bn = 2n - 1 and cn = bn = 2n -1

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#3 2010-06-16 21:56:05

Mariner
Member
Registered: 2010-06-16
Posts: 35

bobbym wrote:

Hi Mariner;

According to the drawing the first rhombus only has 7 dots or vertices, instead of 8. Is that a mistake or is that what they want?

Going by the drawing R4  will have 37 dots.

i'm not sure. I guess you just assume that it's only 7 dots because they have made no effort to add it in or make a note saying it's included:)

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#4 2010-06-16 21:59:14

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Okay, thanks, fair enough!

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#5 2010-06-16 22:04:39

Mariner
Member
Registered: 2010-06-16
Posts: 35

bobbym wrote:

Okay, thanks, fair enough!

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#6 2010-06-16 22:13:56

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Hi; Also there is some ambiguity in the usage of side, to me it means face. R1 has 3 sides. R1 has 3 faces. R1 has 9 edges. Is that what you want?

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#7 2010-06-17 00:04:46

Mariner
Member
Registered: 2010-06-16
Posts: 35

bobbym wrote:

Hi; Also there is some ambiguity in the usage of side, to me it means face. R1 has 3 sides. R1 has 3 faces. R1 has 9 edges. Is that what you want?

just what the question says please, i didn't write them.:D

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#8 2010-06-17 03:13:51

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Side is an ambiguous term in 3D, where it could mean face or edge, but in 2D there's a clear meaning.

R1 is a flat shape made from three rhombuses, R2 is made from 9, and so on.

Now that we're in 2D, talking about perimeter and internal things makes more sense as well.

Why did the vector cross the road?
It wanted to be normal.

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#9 2010-06-17 03:28:21

soroban
Member
Registered: 2007-03-09
Posts: 452

. .

. .

.

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#10 2010-06-17 04:51:13

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Hi Mariner;

just what the question says please, i didn't write them.

Welcome to the forum. I don't agree with the above statements on these grounds. Math is not a spectator sport. I love working on problems and getting them right. I love working on problems and getting them wrong. Because then you get better. That is how you get better. You see there is no down side here. Getting em wrong or getting em right you win. You must try to work on these yourself. You must try very hard. If the problems are done for you then you learn nothing.

Please try to understand what I am saying. Taking shortcuts now means taking the long way later. Trying is everything here. Everyone has problems with math, it's hard. To get better in it is like everything else, practice. So I encourage you to look at what soroban and mathsyperson said and try work it yourself. Posts your tries here and someone will help you.

Thanks for the problem and the enjoyment I got misunderstanding it. Oh, that's another thing, your missing out on lots of fun. Did I say, welcome to the forum?

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#11 2010-06-20 15:32:57

Mariner
Member
Registered: 2010-06-16
Posts: 35

bobbym wrote:

Hi Mariner;

just what the question says please, i didn't write them.

Welcome to the forum. I don't agree with the above statements on these grounds. Math is not a spectator sport. I love working on problems and getting them right. I love working on problems and getting them wrong. Because then you get better. That is how you get better. You see there is no down side here. Getting em wrong or getting em right you win. You must try to work on these yourself. You must try very hard. If the problems are done for you then you learn nothing.

Please try to understand what I am saying. Taking shortcuts now means taking the long way later. Trying is everything here. Everyone has problems with math, it's hard. To get better in it is like everything else, practice. So I encourage you to look at what soroban and mathsyperson said and try work it yourself. Posts your tries here and someone will help you.

Thanks for the problem and the enjoyment I got misunderstanding it. Oh, that's another thing, your missing out on lots of fun. Did I say, welcome to the forum?

Thanks for the warm welcome to the forum:D Now, I need a little help with the worded explanation on the question. I don't quite understand what it wants me to say.

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#12 2010-06-20 16:04:39

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Hi Mariner;

I hoped that you would understand that post. I think you did. Last thing in my heart was to be nasty. Now, what is it that you exactly do not understand. This will help in someone solving your problem. Remember I had difficulties so you may have to wait a bit.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#13 2010-06-20 16:22:18

Mariner
Member
Registered: 2010-06-16
Posts: 35

bobbym wrote:

Hi Mariner;

I hoped that you would understand that post. I think you did. Last thing in my heart was to be nasty. Now, what is it that you exactly do not understand. This will help in someone solving your problem. Remember I had difficulties so you may have to wait a bit.

I don't understand what it wants me to write for a written explanation.

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#14 2010-06-20 16:25:04

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Hi Mariner;

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#15 2010-06-20 16:32:43

Mariner
Member
Registered: 2010-06-16
Posts: 35

bobbym wrote:

Hi Mariner;

my apologies:)

Last edited by Mariner (2010-06-20 16:37:50)

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#16 2010-06-20 16:45:50

Mariner
Member
Registered: 2010-06-16
Posts: 35

Thanks for the help all!

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#17 2010-06-20 17:09:25

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Hi Mariner;

No need for any apologies at all. Do you need help in determining how the various expressions in post #9 were derived? Perhaps it is better the OP answer that but I will do my best to give my explanation, if you will keep in mind that I originally did not get all the right answers.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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