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Topic: Simplifying Algebraic Expressions with Subtracted Expressions
Replies: 67   Last Post: Nov 25, 2013 12:57 PM

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Robert Hansen

Posts: 7,696
From: Florida
Registered: 6/22/09
Re: Simplifying Algebraic Expressions with Subtracted Expressions
Posted: Nov 14, 2013 1:44 PM
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On Nov 14, 2013, at 12:51 PM, Joe Niederberger <niederberger@comcast.net> wrote:

> Lou Talman says:
>> Here is one such problem, as given by Ma: "Mrs. Chen made
> some tarts. She sold 3/5 of them in the morning and 1/4 of the remainder in the afternoon. If she sold 200 more tarts in the morning than in the afternoon, how many tarts did she make?"
>
> LiPing Ma goes on to illustrate the "solution" as a working out of this "starting point" arithmetic expression: 200 % (3/5 - 1/4(1-3/5)).
>
> What is the thought process that guides the formation of such an expression? Or, what is an English translation of that expression that relates naturally to the word problem as given? Is there any way to do so without mentioning the implicit "x"?
>
> Cheers,
> Joe N



I thought that at first as well, but when you look at the problem a bit (and forget your algebra training) you can see how it is decoded in one pass (without an implicit x). Look at this problem...

Sam and John were paid 21 dollars total and Sam was paid twice as much as John, how much were each paid?

We tend to look at this as S + J = 21 and S = 2J, but you can literally (without some implicit x) see this as John and 2 Johns equal 21 and thus John = 7.

The Ma problem works the same way, through literal substitution...

3/5 {morning batch)

minus

1/4(1-3/5) {evening batch} <- This is the literal interpretation of what was written.

equal

200


Bob Hansen


Date Subject Author
11/11/13
Read Simplifying Algebraic Expressions with Subtracted Expressions
MVTutor
11/11/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/12/13
Read Re: Simplifying Algebraic Expressions with Subtracted
Expressions
Bishop, Wayne
11/12/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
MVTutor
11/13/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Jonathan Crabtree
11/13/13
Read Re: Simplifying Algebraic Expressions with Subtracted
Expressions
Bishop, Wayne
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Louis Talman
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted
Expressions
Bishop, Wayne
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted
Expressions
Bishop, Wayne
11/14/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Pam
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted
Expressions
Bishop, Wayne
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/17/13
Read Re: Simplifying Algebraic Expressions with Subtracted
Expressions
Bishop, Wayne
11/17/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/17/13
Read Re: Simplifying Algebraic Expressions with Subtracted
Expressions
Bishop, Wayne
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Pam
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/15/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Pam
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/18/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Louis Talman
11/21/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/21/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Louis Talman
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Pam
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Pam
11/16/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/18/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
GS Chandy
11/17/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
GS Chandy
11/17/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Pam
11/17/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/17/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Pam
11/17/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/17/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Pam
11/18/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/18/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/18/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Pam
11/18/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/25/13
Read Re: Simplifying Algebraic Expressions with Subtracted
Expressions
Bishop, Wayne
11/25/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/22/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Joe Niederberger
11/25/13
Read Re: Simplifying Algebraic Expressions with Subtracted
Expressions
Bishop, Wayne
11/23/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
GS Chandy
11/24/13
Read Re: Simplifying Algebraic Expressions with Subtracted Expressions
Robert Hansen
11/25/13
Read Re: Simplifying Algebraic Expressions with Subtracted
Expressions
Bishop, Wayne

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