My TI-83 Plus says the answer is 9.  So that is what it shall be!

9

...

left to right... 9

horribly written expression if 9 is the answer you are looking for.

I'm conditioned to treat that 2(1+2) as the whole denominator as this is a parathesis function.  Theres a difference between a(b+c) and a*(b+c).  Therefore I came up with an anwer of 1.

My TI-85 must think the same way as plugging 6/2(1+2) spits out a 1.

Plugging the expression directly into excel gives an error and rewrites itself to add the *, then gives a 9.

Entering 6/2*(1+2) on the TI-85 then gives you a 9 as expected.

I'm noticing a trend in these questions and answers.

It seems since electronic calculators have entered the scene, order of operations rules have been subordinated to the limitations of the earliest calculator programming.

When I was taught algebra (early 1980's), we had to memorize order of operations by brute force without pneumonic devices and we were forbidden the use of electronic devices (they were available, but not to be used until the basics were understood).

In college it was the same thing. I completed algebra, pre-calculus, calculus, and made it through a chemistry major with physics and earth science minors and a graduate degree in engineering managment with the order of operations I was taught.

Am I saying that order of operations has changed? Yes, in my observation.

When things were done only by hand, the fewer symbols used the faster caculations were done. Thus, much effort went into what to do with operations using a minimum of symbols. Now, more symbols allows more programming precision, and caculations using electronics are instantaneous. So order of operations seems to be subordinated to limitations in notations in a calculator. The changes are very subtle, but I definately see an old school vs. new school difference in the answers. I discussed this issue at work with a young woman who just completed her degree in mathmatics and she seemed to agree.

The way I was taught 6 ÷ 2 ( 1 + 2 ) translates to 1, but I have no problem if the rules have changed and the answer is 9; all I want to know what is considered the proper way to calculate things today, as agreed upon by the mathmatics regulatory bodies.

Nine

This is how I interpeted it
6    
2(2+1)
getting 1 as the result

What I'm worried about is how people answered 6.

I got it wrong, looked at it as    
  6
                                             
-----------
                                             
 2*(2+1)

yep, I was wrong.

maybe a better way to think of it would be....

6*(1/2)*(2+1)

I wanted to put it in Maple to see what it would spit out,  funny thing is on my screen in Maple it says

"6÷2(1+2)    
                     9"

But when I copy paste (control c, control v) it spits out this

> (6*(1/2))*(2+1);
print(`output redirected...`); # input placeholder
                              9

you ever take a single aimed shot at ssomething very far away? algebra out the ass not to mention trig, radians, and so on





 

I didn't notice this the first time around.  Anyone who thinks any form of math should not be taught in school hasn't really thought it through or would prefer living in the stone age.  Every single thing in modern times was developed with the use of math.  Doing without math It would be like trying to write a bible without letters, or paint a picture without paint.  Math is what makes the world go round (well at least allows us to explain it).  Algebra is the language of math, and all higher forms of math use algebra.  If it was not required, it would not be taught.  It is required in order to expose enough of the population to it, with the hope that some understand it and excel in it.  Later those students become the scientist/engineers/inventors and society continues to advance.  People tried for years to do without, many people were even killed to keep math/science down; technological advancement moved slower than a snails pace.  

Something else that I've seen (now that I have kids in school); is the constant attempt to water down math.  It is to the point where I am starting to believe it is a great conspiracy to dumb down the population (not really, but one could make the jump).  Fractions seem to be some cosmic waste of time.  Everyone wants to make them a decimal.  Then what happens in trig, calc, diff eq, and so on when people don't understand them?  Fractions are so simple, but people are being taught to fear them.  More time is being spent on calculators than learning basic math.  What happens to those students when they become engineers and they depend purely on the calculator to asses validity of answers.  We misplace a decimal place or two and then don't hit Mars.  

Poorly written equation.  You will get two different answers using different programs.

Actually, the way it's written in the title now is good to go.  Before, the "÷" was a "/" and made it ambiguous because you couldn't determine if it was a division symbol or a fraction line written in-line.

Man oh man.

Short answer? There is no correct answer. Or rather, the correct answer is: “undefined”. This is like asking “How heavy is a building?”. There is no right or wrong answer, the question is not specific enough to resolve to one single answer. Maybe a more accurate analogy is giving someone directions. The way this problem is worded,  you have told us “you’re going to drive 2 miles, turn, drive 1 mile, turn, drive 3 miles, turn, then drive 1 mile. You will be taking 2 lefts and one right turn”. You’ve given the basic info we need, but without a little more organization we can’t do anything with it. This is one of the shortfalls or attempting to write mathematical expressions on a single line using the standard ascii symbols. To be specific enough, you often need to use a cumbersome amount of parentheses, brackets, etc. There are two possible interpretations to what you have written:

6/[2(1+2)] = ?

Or

(6/2)(1+2) = ?

Without more information than you have given, there is no way to determine which interpretation is intended, and as such no way to give an answer. The fact that some have gotten an answer on their calculator means nothing. Depending on the calculator and its method of input you can get both possible answers (9 or 1). I believe someone above referenced a calculator using RPN (Reverse Polish Notation) in which you could get BOTH answers depending on which (equally valid) order you entered the terms and operators. This is a limitation of calculators, and the reason I heavily discourage their use in my classes. The calculator operates based on a set of rules, with no interpretation. If you input an ambiguous expression, it will be happy to give you a solid answer, the old “garbage in, garbage out” adage. Similarly, the old order of operations mnemonic device PEMDAS is not a law or rule… it is an extremely simplified acronym that attempts to condense the complex interrelationships of the commutative, distributive, and other properties of binary operations and conditional logic into a simple form that most high school students can remember. Blindly relying on it without a full understanding of the underlying principles can be problematic. So in summation, there is no correct answer, as there is no valid question to be answered.

My credentials:
PhD in Mechanical Engineering
Employed in the space/defense industry
Several years teaching experience, undergraduate and graduate level engineering and math courses

I voted wrong in the poll.

I'm here to erase my answer and change it to 9.

I voted right in the poll but am here to vote again to make sure I'm right

It's 9



And Im only here because someone said there was actually a MATH forum





I'll be ding-danged , there is

The answer is 9.

My credentials:
6th grade math teacher who doesn't over analyze simple questions.

The answer is 9, the rules are clear, however I was taught that it is poor form to write a question where one must rely so heavily on the knowledge of the order of operations in order to arrive at the correct answer. Math is a language. Speak clearly. Just as a wall of text post with everything spelled correctly and all the i's dotted and t's crossed isn't the best way to convey a thought, a poorly constructed math problem isn't the best way to ask a question. You do have to worry about people making a mistake on this when they are in a hurry, so it's worth the time to write it in a non-confusing manner (just as it is worth the time to write arcsine(x) instead of sin^-1(x)).

eta: my credentials - mathematics major, masters of science in electrical engineering, Ph.D. student.

Correct.  Fools think it's '1'
 

Its 1
Solving the bracket first(1+2) gives 3. Multiplying 2 and 3 gives 6. Then dividing 6 by 6 gives 1

1001B

Real engineers stopped using old school divide symbol a long time ago.
Order of ops in the denominator. Answer is 9.

You cant forget that distribution occurs simultaneously as Parenthesis!

288

I first thought that the answer was 1.  After reconsidering, I realized that I had multiplied (2+1) by 2 before dividing into 6.  Since multiplication and division have the same precedence, I should have evaluated the problem from left to right after adding the expression in the parenthesis.  This gives an answer of 9.



At least, I believe that this is the current convention.  If I'm wrong, I trust that someone will say so, and why.

...

You can be a clever as you want, but I would either mark you down (home work) or tell you to correct it (real life)?

So the answer from me is, "You didn't write this well enough to meet my approval."

Well I got "1", so obviously the real answer must be "9".

I bet this stuff is how rockets blow up and/or crash into shit.

Speaking of ambiguous, do you really mean you could care less or do you mean you could NOT care less?

This.  Parens first, then left to right mult/div.  So 6/2(1+2) = 6/2*3 = 3*3=9

FPNI

I'm willing to bet that is not what you were taught.  However, if you were, you were taught wrong.  The order of operations has not changed.  People simply forget that multiplication and division are "equals", as well as addition and subtraction.

Calculus, at least at the lower levels, isn't really hard IMO - not the calculus itself.  What's hard is the algebra and trig you have to know in order to do the calculus, and figuring out how to convert a word problem into a function.



If you're curious about things, and know some math, it can be pretty useful.  If either of these don't apply, and you don't need it for your job, you're more likely IMO to not see a use for it.



BTW, if you're finishing Calc I now, that probably means you're taking it in a condensed summer semester format... I'm glad I didn't try that

 

As written PEMDAS.... =9


But it all matter how you view that as written on paper.

Video is stupid.

When being taught PEMDAS, you are also taught left to right and multiplication and division are switchable and so are addition/subtraction

Oh look, I'm in Math 75 too!
I also got 9.

Solve: 6÷2(1+2)

Expand implicit multiplication notation for clarity: 6 ÷ 2 * (1+2)

Resolve Parenthesis: 6 ÷ 2 * 3

Resolve remaining multiplication and division - Step 1: 3 * 3

Resolve remaining multiplication and division - Step 2: 9



Solve: 6÷2(1+2) using distribution because you're bored...

Resolve external terms: 3(1+2)

Distribute external term: 3+6

Add: 9



Nine is the correct answer to the problem as expressed.



Alternate problem:

Solve: 6÷2(1+2)^-1 (correct notation if you expect a 1)

Expand implicit notation for clarity: 6 ÷ 2 ÷ (1+2)

Resolve Parenthesis: 6 ÷ 2 ÷ 3

Resolve remaining multiplication and division - Step 1: 3 ÷ 3

Resolve remaining multiplication and division - Step 2: 1



Solve: 6÷(2(1+2)) (alternate correct notation if you expect a 1)

Expand implicit notation: 6÷(2 * (1+2))

Resolve first parenthesis: 6÷(2 * 3)

Resolve next parenthesis: 6÷6

Divide: 1



Remind me to put this down as a question in future job interviews...

pjoo1120

Actually since the numbers were 6 & 2 that would make no difference..
6 divided by 2 equals 3
6 halves are equal to 3

That dude should stick to pop science "physics" garbage and stay out of basic mathematics.

He's completely, entirely, 100% wrong.

Ya'll's postin' in a troll thread!



Answer: 9.