Author Topic: A math problem.  (Read 8614 times)

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stargazer

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Re: A math problem.
« Reply #45 on: November 02, 2012, 12:08:40 PM »
The correct answer will not be posted until tomorrow night.  It is causing quite a stir on the FB radio stations page.  Anyone game?

6-1x0+2 divided by 2=?

I have no symbl on my keyboard for divide that I can see.

Is it

6 - 1 x 0 +2 2 =

or

6 - 1 x 0 + 2
--------------- =
        2

That is important.  I read it as the second way and got 4.  If it's written the other way than the answer is 7.   This is why math has rules.

Girlie

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Re: A math problem.
« Reply #46 on: November 02, 2012, 12:10:22 PM »
A FB friend of mine posted this link on her wall last night. I've been following it, too, just because I like seeing how everyone answers. It's funny how so many people can be so adamant about the wrong answer.
Perhaps the point is to prove to us that maybe we're not all as smart as we think we are? That maybe things we know for absolute certain to be true could possibly be false? (I really don't know their "why," I'm just taking what I get out of it).

Anyway, my mom and MIL each answered 1.
My husband and one of my co-workers answered 5.
I'm going with 7.

Geekychick1984

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Re: A math problem.
« Reply #47 on: November 02, 2012, 12:15:30 PM »
Another math geek here.  The answer is 7 (and my math geek husband agrees).  Order of operations = multiplication and division before addition and subtraction.  I learned this in middle school...

Judah

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Re: A math problem.
« Reply #48 on: November 02, 2012, 12:19:41 PM »
The thing I've always liked most about math is that it completely unambiguous. Though there might be more than one way to arrive at the correct answer, there is one correct answer, and opinions and feeling don't come into the equation. 
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Aeris

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Re: A math problem.
« Reply #49 on: November 02, 2012, 12:21:37 PM »
I (and DH) learned absolutely unquestionably without parenthesis ones does math in order left to right.  So as written the answer is 1.

If written 6 - (1X0) + (2/2) it would be 7.

You're telling me neither you nor your DH learned the order of operations? That's very odd.

http://www.math.com/school/subject2/lessons/S2U1L2DP.html

You just linked a page explaining order of operations. WillyNilly is saying that she and her DH learned to do the whole thing from left to right, instead of doing multiplication/division left to right first, then addition/subtraction left to right afterwards. Which means WillyNilly is saying that neither she nor her DH were taught the order of operations. Which I find odd.

Odd as it may be, that's what I was taught, and that's what DH was taught.  That's why parenthesis are used (or at least it was always my understanding) - to show you in this case its not left to right, in this example you do these bits first.  Otherwise why ever bother with using parenthesis?  If its always multiplication first the parenthesis are extraneous. 

And it should be noted both DH and I went to high school in different states (me NY him CT) so this was across curriculums.

And this all really explains why people hate math with such burning passions.  Its not clear or intuitive, or taught in universally similar ways.  In fact I just asked my dad, a (now retired, and admittedly not math) teacher for over 35 years and he said "left to right if no parenthesis".

It makes me weep for the state of education, since the only explanation is that you, your DH, and your father all apparently had completely incompetent math teachers.

This is not just a difference in how people teach math. It's fundamental deficiency at a fairly basic level. The rule that multiplication takes precedence over addition has been around since about the 1600s - when the basic concepts of algebraic notation were first being developed.

MOM21SON

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Re: A math problem.
« Reply #50 on: November 02, 2012, 12:22:07 PM »
A FB friend of mine posted this link on her wall last night. I've been following it, too, just because I like seeing how everyone answers. It's funny how so many people can be so adamant about the wrong answer.
Perhaps the point is to prove to us that maybe we're not all as smart as we think we are? That maybe things we know for absolute certain to be true could possibly be false? (I really don't know their "why," I'm just taking what I get out of it).

Anyway, my mom and MIL each answered 1.
My husband and one of my co-workers answered 5.
I'm going with 7.

Isn't this the truth.  The range in answers is amazing and I have a feeling there will be lots of different people disappointed and maybe slightly embarrassed for the Way they responded.

Luci

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Re: A math problem.
« Reply #51 on: November 02, 2012, 12:25:54 PM »
The thing I've always liked most about math is that it completely unambiguous. Though there might be more than one way to arrive at the correct answer, there is one correct answer, and opinions and feeling don't come into the equation.

Thank you.

Bexx27

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Re: A math problem.
« Reply #52 on: November 02, 2012, 12:28:32 PM »
This thread is hurting my brain. Math actually does have universal rules and the order of operations is one of them. If you solve the problem as written following the order of operations correctly, the answer is 7. It's not open to interpretation. I don't think people are stupid or uneducated for getting it wrong; it's more than understandable not to remember math you learned as a kid (and likely haven't used or thought about for many years) with perfect accuracy. I've forgotten probably 90% of what I learned in school (sigh). That's why shows like "Are You Smarter Than a 5th Grader" are fun - we know adults aren't stupid for not knowing the answers to elementary level questions.

I really doubt anyone was taught to solve math problems from left to right regardless of PEMDAS. I think people are misremembering and were actually taught to solve left to right when the order of operations does not apply, for example x+y+z. Again, that doesn't make anyone less intelligent, but it also doesn't make them less incorrect, and it doesn't mean that math rules are ambiguous.
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onyonryngs

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Re: A math problem.
« Reply #53 on: November 02, 2012, 12:38:33 PM »
You can use / to signify a divide symbol.  Here's the answer via a Google search if you're not agreeing with the math  http://www.weegy.com/?ConversationId=D589CE7B  - because if it's on the internet, it must be true.

Lynnv

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Re: A math problem.
« Reply #54 on: November 02, 2012, 12:39:39 PM »
The correct answer will not be posted until tomorrow night.  It is causing quite a stir on the FB radio stations page.  Anyone game?

6-1x0+2 divided by 2=?

I have no symbl on my keyboard for divide that I can see.

Is it

6 - 1 x 0 +2 2 =

or

6 - 1 x 0 + 2
--------------- =
        2

That is important.  I read it as the second way and got 4.  If it's written the other way than the answer is 7.   This is why math has rules.

I agree-it does make a difference if it is written the second way rather than the first.  I stand by my 7, but will agree that it should be 4 if it was written the other way.

I never even thought of the second as a possibility.  The nature of the problem (learning order of operations) makes me think that it was probably written the first way, but that is just an assumption on my part and could be completely wrong. 
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MariaE

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Re: A math problem.
« Reply #55 on: November 02, 2012, 02:09:36 PM »
The correct answer will not be posted until tomorrow night.  It is causing quite a stir on the FB radio stations page.  Anyone game?

6-1x0+2 divided by 2=?

I have no symbl on my keyboard for divide that I can see.

Is it

6 - 1 x 0 +2 2 =

or

6 - 1 x 0 + 2
--------------- =
        2

That is important.  I read it as the second way and got 4.  If it's written the other way than the answer is 7.   This is why math has rules.

I agree-it does make a difference if it is written the second way rather than the first.  I stand by my 7, but will agree that it should be 4 if it was written the other way.

I never even thought of the second as a possibility.  The nature of the problem (learning order of operations) makes me think that it was probably written the first way, but that is just an assumption on my part and could be completely wrong.

That's true. I assumed it was the former as well, as that would seem to follow the form of all the similar problems going around facebook, but it is true that it is an assumption.

If it turns out it was meant to be the latter, the answer is 4.
 
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joraemi

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Re: A math problem.
« Reply #56 on: November 02, 2012, 02:16:49 PM »
I kind of wondered if the station was doing this to point out how much we forget after 5th grade.  lol




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PastryGoddess

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Re: A math problem.
« Reply #57 on: November 02, 2012, 02:21:06 PM »
PastryGoddess, you have an oops, I think.  In 6 - 0 + 1, you can't reduce that to 6 - 1, it would be 6 + 1.  The - is attached to the 0 (it's the same as saying 6 + -0 + 1.  So you would get 7 instead of 5.


since when can 0 be negative?  Please explain or link to a page explaining.  Since addition comes before subtraction I added 1 to 0 then subtracted 6 from there. 


http://www.math.com/school/subject1/lessons/S1U1L10DP.html

0 doesn't need to be negative to follow this. "6-0+1" is just "take nothing away from 6 and then add 1".  Zero operates the same way as any other number.

Ah I see.  It was the - in front of the 0 that threw me off.  Thanks for the clarification Iris :D

ilrag

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Re: A math problem.
« Reply #58 on: November 02, 2012, 02:31:52 PM »
I (and DH) learned absolutely unquestionably without parenthesis ones does math in order left to right.  So as written the answer is 1.

If written 6 - (1X0) + (2/2) it would be 7.

You're telling me neither you nor your DH learned the order of operations? That's very odd.

http://www.math.com/school/subject2/lessons/S2U1L2DP.html

You just linked a page explaining order of operations. WillyNilly is saying that she and her DH learned to do the whole thing from left to right, instead of doing multiplication/division left to right first, then addition/subtraction left to right afterwards. Which means WillyNilly is saying that neither she nor her DH were taught the order of operations. Which I find odd.

Odd as it may be, that's what I was taught, and that's what DH was taught.  That's why parenthesis are used (or at least it was always my understanding) - to show you in this case its not left to right, in this example you do these bits first.  Otherwise why ever bother with using parenthesis?  If its always multiplication first the parenthesis are extraneous. 

And it should be noted both DH and I went to high school in different states (me NY him CT) so this was across curriculums.

And this all really explains why people hate math with such burning passions.  Its not clear or intuitive, or taught in universally similar ways.  In fact I just asked my dad, a (now retired, and admittedly not math) teacher for over 35 years and he said "left to right if no parenthesis".

It makes me weep for the state of education, since the only explanation is that you, your DH, and your father all apparently had completely incompetent math teachers.

This is not just a difference in how people teach math. It's fundamental deficiency at a fairly basic level. The rule that multiplication takes precedence over addition has been around since about the 1600s - when the basic concepts of algebraic notation were first being developed.

As a math minor (physics major) in college, former high school math teacher and current engineer I have to assume that WillyNilly, her DH and her dad were all taught the correct order of operations in school, but since that doesn't come up in their daily life they just forgot about it.

There's no way it wasn't mentioned in school. 

Think about all of the things you've forgotten. (Dates that are important in history, monologues from Shakespeare, grammar rules you never use, how to graph a quadratic equation). This idea just didn't stick with everyone. 

WillyNilly

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Re: A math problem.
« Reply #59 on: November 02, 2012, 02:44:28 PM »
Of course its possible we just forgot it, but I do remember left to right being emphasized (possibly just for addition & subtraction) and I do remember parenthesis being emphasized (and my dad even specifically mentioned parenthesis) so even if we were taught the order of operations it wasn't emphasized as much as the other two.