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Re: 6�2(1+2)=?
I believe that using the order of operations, the answer would be 9. PEMDAS (some say GEMDAS-G standing for grouping symbols) says that the order of operations = parenthesis, exponents, multiplications OR divisions-left to right-whichever comes first, finally additions OR subtractions -left to right-whichever comes first.

Beetlemess is right. The other ways of working it out, like the one on Facebook have mathematical flaws. They do not really follow the order of operations. There's a bit of math sleight of hand going on. Beetlemess elegantly listed all of the steps and reasons why it should be worked so that the answer is 9.

Tina, the Facebook thing is just not correct math.
"If it were written 6 / 2 x 3 the answer would be 9
but if the 3 were an x and it were written 6/2x, the answer would be 1."

6/2 = 3 and 3*x = 3x it does not equal 1 As a variable, x could equal any number.
if you had 3x/3x that would equal 1.

Some people think that PEMDAS means you do the multiplication first. Those folks would think that they would do the 2 * 3 first and then divide by 6. That would give them 1, but it would be incorrect.

The distributive property does need to be taken into account. However, first do what is in the parenthesis. Then, the division is completed. After that, you distribute the 3 times the 3 for an answer of 9.

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Try This go to [url=http://www.freemathhelp.com/distributive-property.html]free math help / distributive property[/url] and type in 6/2(1+2)=x and hit solve it will show you how they got their answer

old school #682621 04/30/11 03:00 PM
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I visited the above site and it worked. Go to the bottom of the page and type in the math problem, hit answer and the problem will be solved for you.

Free Math Help


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I stand corrected.... If you type in 6/2(2+1)=x and hit solve, the answer is x=1 If you type in 6/2(2+1) and hit solve, the answer is 9 ...I give up!

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I stand corrected.... If you type in 6/2(2+1)=x and hit solve, the answer is x=1 If you type in 6/2(2+1) and hit solve, the answer is 9 ...I give up!

old school #682647 04/30/11 05:30 PM
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Yes, if it were written 6 / 2 x 3, the answer would be 9.

But it isn't written that way. And when you write 2(1+2), the whole thing is an expression that needs to be treated as a unit in terms of any other operations.

The expression 2(2+1) equals to 6 and needs to be treated as if it were the number 6.

If you were using letters a and b instead of the 2 and 1 in the parentheses, it would be 2(a+b). This is a tidy way of writing (2a + 2b) because it's treated as a unit. Plugging the numbers back in, it would be the sum of 2x2 (4) and 2x1 (2), i.e., 6.

6 divided by 6 is 1.

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I'm not moved from my "9" stance.

6 divided by 2 times the quantity 1+2 is calcualted in that order...

Had the equation been
6/(2(1+2)) => then it would be 6 divided by the quantity of 2 time the quantity of 1+2.

But since there are no parens to define a calculated quantity for the denominator, only the numerical value can be used.


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Beetlemess #683071 05/02/11 01:27 PM
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You don't have to put the 2(1+2) into further brackets, because without an operator between the 2 and the (1+2), it is always read as one expression which, in this case, equals 6.

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Mona, I have to say that I do agree with you. I remember teaching my own kids algebra. According to the way they were taught and what the answer keys said, the correct answer would be 1.


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I really do not see what all the confusion is about.

Beetlemess mentioned the "Order of Operations" which is very clear. The Order of Operations states that if there is a problem that has all of the following operations: Parentheses, Exponents, Multiplication, Division, Addition and Subtraction, then the Operations must be performed in the order in which they are stated. Therefore, 6�2(1+2)= 9.

"It seems as though the answer depends on which way you look at the problem. But we can't have this kind of flexibility in mathematics; math won't work if you can't be sure of the answer, or if the exact same problem can calculate to two or more different answers. To eliminate this confusion, we have some rules of precedence, established at least as far back as the 1500s, called the "order of operations". The "operations" are addition, subtraction, multiplication, division, exponentiation, and grouping; the "order" of these operations states which operations take precedence (are taken care of) before which other operations.

A common technique for remembering the order of operations is the abbreviation "PEMDAS", which is turned into the phrase "Please Excuse My Dear Aunt Sally". It stands for "Parentheses, Exponents, Multiplication and Division, and Addition and Subtraction"."

See: Order of Operations


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