Okay Math Geniusues... What's 48÷2(9+3) ?

[kjc]

Originally Posted by 107barney

Teddy has 288 biscuits !

Blah, blah, blah, blah... can't have stuff that ain't there! That's fine.... 288 is good. You hiring by any chance (but only if you do your own payroll.. hehehe.)

[JMuedog]

LOL! Look at this:

http://i56.tinypic.com/16h6ja8.png

I say it means that We're all CORRECT!

[Wylie's Mom]

Originally Posted by JMuedog

LOL! Look at this:

http://i56.tinypic.com/16h6ja8.png

I say it means that We're all CORRECT!

Oh boy. I haz confuzed.

[kjc]

x=
()= ( means that one multiplies! FOIL (First, inner, outter, last)

[Nancy1999]

This isn't a math problem as much as it is a reading problem. The question asks, "What is 48 divided by two times the sum of 9 plus 3?" It does not ask, what is 48 divided by 2, multiplied by the sum of 9 plus 3.

[OwnedByJezebel]

Originally Posted by Nancy1999

This isn't a math problem as much as it is a reading problem. The question asks, "What is 48 divided by two times the sum of 9 plus 3?" It does not ask, what is 48 divided by 2, multiplied by the sum of 9 plus 3.

[Rhetts_mama]

Originally Posted by JMuedog

LOL! Look at this:

http://i56.tinypic.com/16h6ja8.png

I say it means that We're all CORRECT!

You know things are confuzzled when even the calculators can't agree

[BabyGirl Rosie]

I had fun with this in my classroom today. I had my 8th grade Algebra students work it. These are advanced students. Three answers came out of the problem. 288, 2, and 8 1/3. Hmmmmmm. My calculator, the TI 73, shows 288. I said in my post that it is 288 if you follow order of operations. (And I teach math. lol). I asked math teacher friends. They got 288. BUT if you look at it as a fraction bar for division it creates a whole different situation. Because fraction bars fall under the grouping symbols. If you use the fraction bar, the answer is 2. I have taught order of operations for years. Never had a problem stump me like this. I think it depends on how you write it. Fraction bar is 2 for sure. Urrrrrgghh this will end up driving me nuts!

[IMG]file:///C:/Users/Rhonda/AppData/Local/Temp/moz-screenshot.png[/IMG]

[MaddiesMommie]

Originally Posted by JMuedog

LOL! Look at this:

http://i56.tinypic.com/16h6ja8.png

I say it means that We're all CORRECT!

HaHa! Found this :
Note that different software will process this differently; even different models of Texas Instruments graphing calculators will process this differently. In cases of ambiguity, be very careful of your parentheses, and make your meaning clear. The general consensus among math people is that "multiplication by juxtaposition" indicates that the juxtaposed values must be multiplied together before processing other operations.
purplemath.com

[Nancy1999]

Originally Posted by BabyGirl Rosie

I had fun with this in my classroom today. I had my 8th grade Algebra students work it. These are advanced students. Three answers came out of the problem. 288, 2, and 8 1/3. Hmmmmmm. My calculator, the TI 73, shows 288. I said in my post that it is 288 if you follow order of operations. (And I teach math. lol). I asked math teacher friends. They got 288. BUT if you look at it as a fraction bar for division it creates a whole different situation. Because fraction bars fall under the grouping symbols. If you use the fraction bar, the answer is 2. I have taught order of operations for years. Never had a problem stump me like this. I think it depends on how you write it. Fraction bar is 2 for sure. Urrrrrgghh this will end up driving me nuts!

[IMG]file:///C:/Users/Rhonda/AppData/Local/Temp/moz-screenshot.png[/IMG]

Back in the olden days we were taught to do the insides of parenthesis first, and then do what ever it takes to get rid of parenthesis. In other words, add 9+3 first and you still have parenthesis.
48÷2(12)
In order to get rid of that parenthesis you have to multiply, after you multiply, you can get rid of parenthesis and you have a problem that can be worked from left to right.

48 ÷ 24

Do they still teach that rule about parenthesis?

[lisaly]

Originally Posted by Nancy1999

Back in the olden days we were taught to do the insides of parenthesis first, and then do what ever it takes to get rid of parenthesis. In other words, add 9+3 first and you still have parenthesis.
48÷2(12)
In order to get rid of that parenthesis you have to multiply, after you multiply, you can get rid of parenthesis and you have a problem that can be worked from left to right.

48 ÷ 24

Do they still teach that rule about parenthesis?

You are doing what's in the parenthesis first. Otherwise you'd be multiplying by 9 and then adding 3 afterwards. The parenthesis must come first. I showed this to my wonderful assistant, and we had fun with this, but we were too busy in our Resource Room working on and having our students take a two part Geometry proof test that took precedence. I love working with kids on Algebra, but Geometry is not fun for most of us.

[MaddiesMommie]

Originally Posted by Nancy1999

Back in the olden days we were taught to do the insides of parenthesis first, and then do what ever it takes to get rid of parenthesis. In other words, add 9+3 first and you still have parenthesis.
48÷2(12)
In order to get rid of that parenthesis you have to multiply, after you multiply, you can get rid of parenthesis and you have a problem that can be worked from left to right.

48 ÷ 24

Do they still teach that rule about parenthesis?

Yes, we do and you are correct, you must multiply the sum of the parentheses by 2 to get rid of them.

[Nancy1999]

Originally Posted by lisaly

You are doing what's in the parenthesis first. Otherwise you'd be multiplying by 9 and then adding 3 afterwards. The parenthesis must come first. I showed this to my wonderful assistant, and we had fun with this, but we were too busy in our Resource Room working on and having our students take a two part Geometry proof test that took precedence. I love working with kids on Algebra, but Geometry is not fun for most of us.

Lol, yes, I said do the insides of parenthesis first!

[Nancy1999]

Originally Posted by MaddiesMommie

Yes, we do and you are correct, you must multiply the sum of the parentheses by 2 to get rid of them.

Thank you!

[BabyGirl Rosie]

Originally Posted by Nancy1999

Back in the olden days we were taught to do the insides of parenthesis first, and then do what ever it takes to get rid of parenthesis. In other words, add 9+3 first and you still have parenthesis.
48÷2(12)
In order to get rid of that parenthesis you have to multiply, after you multiply, you can get rid of parenthesis and you have a problem that can be worked from left to right.

48 ÷ 24

Do they still teach that rule about parenthesis?

This is what it says in Prentice Hall Algebra book:

1. Perform any operation inside grouping symbols
2. Simplify the powers
3. Multiply and Divide in order from left to right.
4. Add and subtract in order from left to right.

To me, this is saying once the 9 + 3 happens then what is left is considered multiplication. The two is distributive property which in reality is multiplication. Again, I think it is how you set it up. To be honest, I can see it both ways, 2 and 288. I think I need to email one of my old college professors!! It would be interesting to see what they say!!