Math Is Fun Forum

Lorna

Member

Registered: 2014-06-01

Posts: 2

Summation Notation

I am trying to add the following payments for rent over 10 year period $132.62, $133.30, $134.85, $137.00, $137.48, $139.42, $139.74, $141.86, $144.78 and $146.14. I need to write down an equation for the above quantity using Summation Notation and don't know how. There are 52 weeks in a year and not sure how to show equation x52 using summation notation.

Each dollar amount equals what was paid per week for each year from 2004 to 2013. I need to know how to write down an equation for the above quantity using summation notation. The amount $132.62 was for 2004, $133.30 for 2005 etc. I also don't understand how to show it using summation notation x52 weeks each year.

Last edited by Lorna (2014-06-01 21:36:21)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Summation Notation

Hi Lorna;

Those were your monthly payments?

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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.

David

Member

From: Bumpkinland

Registered: 2014-04-23

Posts: 3,164

Re: Summation Notation

I think that is her yearly payments. Sigma Notation? Teach me too bobbym...

Last edited by David (2014-06-01 15:49:56)

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His dominion is an everlasting dominion, Which shall not pass away, And His kingdom the one Which shall not be destroyed.

Agnishom

Real Member

From: Riemann Sphere

Registered: 2011-01-29

Posts: 25,002

Website

Re: Summation Notation

I don't think so.

Hi Lorna;

What is your favorite color?

If you're looking for the sigma notation, it isn't the best idea to represent them.

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'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'
I'm not crazy, my mother had me tested.

David

Member

From: Bumpkinland

Registered: 2014-04-23

Posts: 3,164

Re: Summation Notation

I'm not Lorna, but what notation best represents them?

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His dominion is an everlasting dominion, Which shall not pass away, And His kingdom the one Which shall not be destroyed.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Summation Notation

I do not even know what she wants yet.

---

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.

David

Member

From: Bumpkinland

Registered: 2014-04-23

Posts: 3,164

Re: Summation Notation

Do you know what I want sir? Can you teach me about Sigma? Please?

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His dominion is an everlasting dominion, Which shall not pass away, And His kingdom the one Which shall not be destroyed.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Summation Notation

You mean a little summation calculus or just sigma notation?

---

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.

David

Member

From: Bumpkinland

Registered: 2014-04-23

Posts: 3,164

Re: Summation Notation

The notation

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His dominion is an everlasting dominion, Which shall not pass away, And His kingdom the one Which shall not be destroyed.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Summation Notation

Hi;

Please read this first and follow the links.

http://www.mathsisfun.com/algebra/sigma-notation.html

Ask any question you have after that.

---

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.

Agnishom

Real Member

From: Riemann Sphere

Registered: 2011-01-29

Posts: 25,002

Website

Re: Summation Notation

I'm not Lorna, but what notation best represents them?

I was talkinbg to Lorna. I did not notice your post in between

---

'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'
I'm not crazy, my mother had me tested.

ShivamS

Member

Registered: 2011-02-07

Posts: 3,648

Re: Summation Notation

Hi Lorna;

Those were your monthly payments?

Highly likely that it is weekly.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Summation Notation

Yes, she edited her post.

---

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.

ShivamS

Member

Registered: 2011-02-07

Posts: 3,648

Re: Summation Notation

Oh, I didn't see that.

phrontister

Real Member

From: The Land of Tomorrow

Registered: 2009-07-12

Posts: 4,895

Re: Summation Notation

Hi,

Is the answer something like this?

Sorry, I've never learnt summation notation and researched by following bobbym's link and trying out the Sigma Calculator there, and it gave me the answer I expected to get.

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"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Summation Notation

Hi phrontister;

This is one way:

I truncated all the decimals so that it would fit on 1 line.

Sum[(132.62 + 133.3 + 134.85 + 137 + 137.48 + 139.42 + 139.74 + 
   141.86 + 144.78 + 146.14), {k, 1, 52}]

---

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.

Agnishom

Real Member

From: Riemann Sphere

Registered: 2011-01-29

Posts: 25,002

Website

Re: Summation Notation

that can probably be done but why would you do that?

---

'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'
I'm not crazy, my mother had me tested.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Summation Notation

That is a good question, The summation notation is overkill here.

---

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.

phrontister

Real Member

From: The Land of Tomorrow

Registered: 2009-07-12

Posts: 4,895

Re: Summation Notation

I would just multiply the weekly payments' sum by 52, but Lorna said she needed to know the 'Summation Notation' equation.

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"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

phrontister

Real Member

From: The Land of Tomorrow

Registered: 2009-07-12

Posts: 4,895

Re: Summation Notation

Hi Bobby,

Yes, your notation is what W|A's 'Sigma Notation Calculator' gets too...except that it uses 'n' for 'k', its answer is an integer instead of the true answer, and it rearranged the payments into some other order than the one I gave it.

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"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Summation Notation

Hi;

I truncated the input so it would fit on one line. Use the code instead.

---

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.

phrontister

Real Member

From: The Land of Tomorrow

Registered: 2009-07-12

Posts: 4,895

Re: Summation Notation

Yes, I understood the truncation (I had been disappointed with my messy presentation). And I had used your code in M, but then found W|A's widget. It's still in beta stage, which may explain the unexpected output.

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"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Summation Notation

They have a widget?

---

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.

phrontister

Real Member

From: The Land of Tomorrow

Registered: 2009-07-12

Posts: 4,895

Re: Summation Notation

Yes...see the link I gave to it in post #20.

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"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Summation Notation

It does not do a very good job.

---

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.