math problem

[brooks85]

no i just remember 7th grade math really well

Please
Excuse
My
Dear
Aunt
Sally

haha, I remember learning that like it was yesterday

[rsnnh12]

did you see the screenshot of the TI-86 calculator showing the EXACT question posted here as 288........I guess whoever made the calculator is wrong and you are right.

And the TI-85 had it as 2

Point being, the question is flawed in it's presentation. Personally, I read it so that the answer ended up being 2. But 288 is also a valid answer, depending on your perception... because perception is the key issue here, it means its a flawed question

[OmgUrMom]

no i just remember 7th grade math really well

Please
Excuse
My
Dear
Aunt
Sally

haha, I remember learning that like it was yesterday

multiplacation doesnt come before division unfortunately, they are the same, neither having priority over the other.

this seems to be tripping a lot of people up

[brooks85]

Everyday my faith in people diminishes a little more, thats why I had to stop reading players talk

You have an extremely powerful search engine at your finger tips, use it so you can learn something.

The answer is not 288, so people saying it is "valid" or "also correct" are only encouraging bad habits.

48÷2(9+3) is a horribly written equation because of the ÷ sign but that doesn't change answer.

[8ArIvd5]

multiplacation doesnt come before division unfortunately, they are the same, neither having priority over the other.

this seems to be tripping a lot of people up

but distribution does.

"The Distributive Property is easy to remember, if you recall that "multiplication distributes over addition". Formally, they write this property as "a(b + c) = ab + ac". In numbers, this means, that 2(3 + 4) = 2×3 + 2×4. Any time they refer in a problem to using the Distributive Property, they want you to take something through the parentheses (or factor something out); any time a computation depends on multiplying through a parentheses (or factoring something out), they want you to say that the computation used the Distributive Property.

• Why is the following true? 2(x + y) = 2x + 2y

• Since they distributed through the parentheses, this is true by the Distributive Property.

• Use the Distributive Property to rearrange: 4x – 8

• The Distributive Property either takes something through a parentheses or else factors something out. Since there aren't any parentheses to go into, you must need to factor out of. Then the answer is "By the Distributive Property, 4x – 8 = 4(x – 2)"

"But wait!" you say. "The Distributive Property says multiplication distributes over addition, not subtraction! What gives?" You make a good point. This is one of those times when it's best to be flexible. You can either view the contents of the parentheses as the subtraction of a positive number ("x – 2") or else as the addition of a negative number ("x + (–2)"). In the latter case, it's easy to see that the Distributive Property applies, because you're still adding; you're just adding a negative.
The other two properties come in two versions each: one for addition and the other for multiplication. (Note that the Distributive Property refers to both addition and multiplication, too, but to both within just one rule.)"

[rsnnh12]

Everyday my faith in people diminishes a little more, thats why I had to stop reading players talk

You have an extremely powerful search engine at your finger tips, use it so you can learn something.

The answer is not 288, so people saying it is "valid" or "also correct" are only encouraging bad habits.

48÷2(9+3) is a horribly written equation because of the ÷ sign but that doesn't change answer.

Getting 2 as an answer involves using implicit multiplication (promoted in many text books and some calculators too). Getting 288 does not. There is no official math rule for this, so both answers can be correct

http://mathforum.org/library/drmath/view/54341.html

[8ArIvd5]

Getting 2 as an answer involves using implicit multiplication (promoted in many text books and some calculators too). Getting 288 does not. There is no official math rule for this, so both answers can be correct

http://mathforum.org/library/drmath/view/54341.html

actually, there is a symbol involved, so it would be explicit multiplication. "(" and ")" are both symbols. there is an official rule for this, called the distributive property. read my post above yours.

[rsnnh12]

actually, there is a symbol involved, so it would be explicit multiplication. "(" and ")" are both symbols. there is an official rule for this, called the distributive property. read my post above yours.

Did you read the link? It explains it better than I could

[8ArIvd5]

Did you read the link? It explains it better than I could

yes, i read the link. that's why i used the terms 'explicit' and 'implicit' multiplication. the link is explaining how to multiply and divide when symbols are not involved, but the parentheses are symbols, so your link is irrelevant. did you read my post?

[hhsilver]

And the TI-85 had it as 2 .....

I don't believe this. Are you sure you typed it exactly as given? I am familiar with the TI graphing calculators and if you got 2 , you must have changed the original expression.

LOL.
I don't know if this thread is funny or just sad.

this thread is extremely sad.


Some of the "well written" and verbose explanations are not only wrong but show the various writers' grasps of the concept of "order of operations", along with some other basic math concepts, are poor or nonexistent.

Please google "order of operations" and look for examples like this : 9 ÷ 3 x 3 The answer is 9 NOT 1 as many of you want to believe.

Now look at this one : 9 ÷ 3(1 + 2) The parentheses seem to confuse many of you, but this is the same as the one above and the answer is still 9. There is no need to use the times sign, x, here - it is implicit with the juxtaposition of 3 and ( . However if it were placed between the 3 and ( it wouldn't change a thing. 9 ÷ 3 x (1 + 2) = 9

Here is a copy/paste from this site : http://www.mathgoodies.com/lessons/v...perations.html

Example 3: Evaluate 9 - 5 ÷ (8 - 3) x 2 + 6 using the order of operations.
Solution:
Step 1: 9 - 5 ÷ (8 - 3) x 2 + 6 = 9 - 5 ÷ 5 x 2 + 6 Parentheses
Step 2: 9 - 5 ÷ 5 x 2 + 6 = 9 - 1 x 2 + 6 Division
Step 3: 9 - 1 x 2 + 6 = 9 - 2 + 6 Multiplication
Step 4: 9 - 2 + 6 = 7 + 6 Subtraction
Step 5: 7 + 6 = 13 Addition

In Example 3, you will notice that multiplication and division were evaluated from left to right according to Rule 2. Similarly, addition and subtraction were evaluated from left to right, according to Rule 3.

(end quote)

notice that the part that has (8 - 3) x 2 is slightly different than this thread's original expression in that there is a times sign, X, and the 2 follows the parentheses rather than preceding it. However the above example would yield the same result if that part were written 2 x (8 - 3) or 2(8 - 3) . Remember, the X is unnecessary because of the parentheses and the 2 could be before or after the parentheses because multiplication is commutative.

Now please google "order of operations" and look at more examples.

Some have said there is no rule --- but there is definitely a rule and it is often referred to as "order of operations" . Please use google and learn about it. One of the sites specifically addresses how pemdas or bedmas, etc, confuse students and that is exactly what happened to many of you who refer to those.

[CanuckG]

Everyday my faith in people diminishes a little more, thats why I had to stop reading players talk

You have an extremely powerful search engine at your finger tips, use it so you can learn something.

The answer is not 288, so people saying it is "valid" or "also correct" are only encouraging bad habits.

48÷2(9+3) is a horribly written equation because of the ÷ sign but that doesn't change answer.

[8ArIvd5]

I don't believe this. Are you sure you typed it exactly as given? I am familiar with the TI graphing calculators and if you got 2 , you must have changed the original expression.



this thread is extremely sad.

Seriously, I taught this stuff and I hope I never find out that anyone who thinks the answer is 2 was ever in my class.

Some of the "well written" and verbose explanations are not only wrong but show the various writers' grasps of the concept of "order of operations", along with some other basic math concepts, are poor or nonexistent.

Please google "order of operations" and look for examples like this : 9 ÷ 3 x 3 The answer is 9 NOT 1 as many of you want to believe.

Now look at this one : 9 ÷ 3(1 + 2) The parentheses seem to confuse many of you, but this is the same as the one above and the answer is still 9. There is no need to use the times sign, x, here - it is implicit with the juxtaposition of 3 and ( . However if it were placed between the 3 and ( it wouldn't change a thing. 9 ÷ 3 x (1 + 2) = 9

Here is a copy/paste from this site : http://www.mathgoodies.com/lessons/v...perations.html

Example 3: Evaluate 9 - 5 ÷ (8 - 3) x 2 + 6 using the order of operations.
Solution:
Step 1: 9 - 5 ÷ (8 - 3) x 2 + 6 = 9 - 5 ÷ 5 x 2 + 6 Parentheses
Step 2: 9 - 5 ÷ 5 x 2 + 6 = 9 - 1 x 2 + 6 Division
Step 3: 9 - 1 x 2 + 6 = 9 - 2 + 6 Multiplication
Step 4: 9 - 2 + 6 = 7 + 6 Subtraction
Step 5: 7 + 6 = 13 Addition

In Example 3, you will notice that multiplication and division were evaluated from left to right according to Rule 2. Similarly, addition and subtraction were evaluated from left to right, according to Rule 3.

(end quote)

notice that the part that has (8 - 3) x 2 is slightly different than this thread's original expression in that there is a times sign, X, and the 2 follows the parentheses rather than preceding it. However the above example would yield the same result if that part were written 2 x (8 - 3) or 2(8 - 3) . Remember, the X is unnecessary because of the parentheses and the 2 could be before or after the parentheses because multiplication is commutative.

Now please google "order of operations" and look at more examples.

Some have said there is no rule --- but there is definitely a rule and it is often referred to as "order of operations" . Please use google and learn about it. One of the sites specifically addresses how pemdas or bedmas, etc, confuse students and that is exactly what happened to many of you who refer to those. I always had to have my students unlearn them. They cause students to forget the strict rule concerning left to right for mult and div and for add and subtr.

I realize this thread may die very soon and not many wiil see this post, but if I can show some of those who think the answer is 2 why
48÷2(9+3)= 288 then my time here will have been well spent.

so you're saying the distributive property doesn't exist? and that 48/x(9+3)=576/x?

i think 48/x(9+3)=4x, if it doesn't, explain why or you're wrong.

[LT Profits]

186 replies to what is honestly a third grade question?

And a lot of the answers are wrong??

The correct answer is obviously 2

[excel]

Only at SBR can you turn a poorly written math question into rocket science.

[LT Profits]

we learn it as bimdas in aus. brackets, indices - rest is the same.

the answer is 2. Reasoning below.

"The general consensus among math people is that "multiplication by juxtaposition" (that is, multiplying by just putting things next to each other, rather than using the "×" sign) indicates that the juxtaposed values must be multiplied together before processing other operations."

This is the best explanation

You have to solve the 2(9+3) first.

SO.......

48/2(9+3) = 48/2(12) = 48/24 = 2

Are you smarter than a third grader? Apparently, that is debatable for some SBR posters.

[hhsilver]

so you're saying the distributive property doesn't exist? and that 48/x(9+3)=576/x?

i think 48/x(9+3)=4x, if it doesn't, explain why or you're wrong.

is that x you wrote a multiplication sign? If so what you wrote is not a valid expression. You can never have / and x next to each other with nothing between. Please rewrite your question/comment with valid notation.

[hhsilver]

This is the best explanation

You have to solve the 2(9+3) first.

SO.......

48/2(9+3) = 48/2(12) = 48/24 = 2

Are you smarter than a third grader? Apparently, that is debatable for some SBR posters.

LT -- you are wrong. did you google "order of operations" as I suggested?

in the given expression you absolutely DO NOT evaluate 2(9+3) first.

Please read about "order of operations.

This would be 2 ...... 48/(2(9+3))

[rsnnh12]

I don't believe this. Are you sure you typed it exactly as given? I am familiar with the TI graphing calculators and if you got 2 , you must have changed the original expression.



this thread is extremely sad.

Seriously, I taught this stuff and I hope I never find out that anyone who thinks the answer is 2 was ever in my class.

Some of the "well written" and verbose explanations are not only wrong but show the various writers' grasps of the concept of "order of operations", along with some other basic math concepts, are poor or nonexistent.

Please google "order of operations" and look for examples like this : 9 ÷ 3 x 3 The answer is 9 NOT 1 as many of you want to believe.

Now look at this one : 9 ÷ 3(1 + 2) The parentheses seem to confuse many of you, but this is the same as the one above and the answer is still 9. There is no need to use the times sign, x, here - it is implicit with the juxtaposition of 3 and ( . However if it were placed between the 3 and ( it wouldn't change a thing. 9 ÷ 3 x (1 + 2) = 9

Here is a copy/paste from this site : http://www.mathgoodies.com/lessons/v...perations.html

Example 3: Evaluate 9 - 5 ÷ (8 - 3) x 2 + 6 using the order of operations.
Solution:
Step 1: 9 - 5 ÷ (8 - 3) x 2 + 6 = 9 - 5 ÷ 5 x 2 + 6 Parentheses
Step 2: 9 - 5 ÷ 5 x 2 + 6 = 9 - 1 x 2 + 6 Division
Step 3: 9 - 1 x 2 + 6 = 9 - 2 + 6 Multiplication
Step 4: 9 - 2 + 6 = 7 + 6 Subtraction
Step 5: 7 + 6 = 13 Addition

In Example 3, you will notice that multiplication and division were evaluated from left to right according to Rule 2. Similarly, addition and subtraction were evaluated from left to right, according to Rule 3.

(end quote)

notice that the part that has (8 - 3) x 2 is slightly different than this thread's original expression in that there is a times sign, X, and the 2 follows the parentheses rather than preceding it. However the above example would yield the same result if that part were written 2 x (8 - 3) or 2(8 - 3) . Remember, the X is unnecessary because of the parentheses and the 2 could be before or after the parentheses because multiplication is commutative.

Now please google "order of operations" and look at more examples.

Some have said there is no rule --- but there is definitely a rule and it is often referred to as "order of operations" . Please use google and learn about it. One of the sites specifically addresses how pemdas or bedmas, etc, confuse students and that is exactly what happened to many of you who refer to those. I always had to have my students unlearn them. They cause students to forget the strict rule concerning left to right for mult and div and for add and subtr.

I realize this thread may die very soon and not many wiil see this post, but if I can show some of those who think the answer is 2 why
48÷2(9+3)= 288 then my time here will have been well spent.

http://forum.bodybuilding.com/showpost.php?p=659648193&postcount=3

There's a pic of 2 different TI's, problem entered the same way, different answers. It won't let me post the pic here for some reason.

[CanuckG]

38 votes for 2

Oh dear..

[8ArIvd5]

is that x you wrote a multiplication sign? If so what you wrote is not a valid expression. You can never have / and x next to each other with nothing between. Please rewrite your question/comment with valid notation.

no, x is an unknown. i'll re-write it for you:

48/y(9+3)

simplified is it 576/y or 4/y?

[LT Profits]

LT -- you are wrong. did you google "order of operations" as I suggested?

in the given expression you absolutely DO NOT evaluate 2(9+3) first.

Please read about "order of operations.

This would be 2 ...... 48/(2(9+3))

UM.....how is that different from my answer? We basically both put a parenthesis around everything after the division symbol.

If you want to talk about literal order, first you do the interior parenthesis (9+3) and second you do the exterior parenthesis (2(9+3)) which was implied by the juxtaposition of the 2 to the left of the parenthesis with no symbol.

[hhsilver]

UM.....how is that different from my answer? We basically both put a parenthesis around everything after the division symbol.

If you want to talk about literal order, first you do the interior parenthesis (9+3) and second you do the exterior parenthesis (2(9+3)) which was implied by the juxtaposition of the 2 to the left of the parenthesis with no symbol.

NO --- the 2 next to the ( does not imply a multiplication there because the 2 immediately follows / . this means you must divide what preceded the / by 2 BEFORE multiplying using the result of the division by 2.

/ is division and there are strict unambiguous rules for "order of operations" .

[hhsilver]

no, x is an unknown. i'll re-write it for you:

48/y(9+3)

simplified is it 576/y or 4/y?

it's the same as 48 * (1/y) * (9+3) = 576/y


to get 4/y you could write it as 48/(y(9+3))

[LT Profits]

NO --- the 2 next to the ( does not imply a multiplication there because the 2 immediately follows / . this means you must divide what preceded the / by 2 BEFORE multiplying using the result of the division by 2.

/ is division and there are strict unambiguous rules for "order of operations" .

WRONG, since there is no symbol next to the 2, the juxtaposition rule takes priority.

You are solving for:

48÷2*(9+3), which would be 288

The fact that the equation as stated leaves out the * changes everything. Read the juxtaposition rule earlier in the tread.

[BernardMadoff]

The answer is 288, I majored in electrical and computer engineering, took too much math, if Im wrong Im an idiot. Looks obvious which begs that one should take the opposite oh this is too much like gambling lol.

[underthe total]

The answer is 288, I majored in electrical and computer engineering, took too much math, if Im wrong Im an idiot. Looks obvious which begs that one should take the opposite oh this is too much like gambling lol.

go blazers

[757sFinest]

Can't believe there is a lot of people who have never taken algebra.

[Mistongo]

At 2+2 the percentages are exactly like this but favoring 288.

[Blax0r]

Wow, if folks want to argue the distributive property, then shouldn't you be saying this:

48/2(9 + 3)

24(9 + 3)

288



And, I put this in my TI-89 (which is the TI-85's badass big brother), and got 288 w/ and w/o the multiplication symbol.

[Full Time Hobo]

Only at SBR can you turn a poorly written math question into rocket science.

[Kaabee]

just type it in google search box. google is wicked smart, it knows about order of operations.

[tenbas]

Everyone who has just a little mathematical education knows that 48/2(9+3) is 288. There is no confusion here.
Ask some mathematicians.
LT Profits = go to the special olympics, you are a disgrace.

Also, if you are not sure about something mathematical, use this:

http://www.wolframalpha.com/input/?i=48%2F2%289%2B3%29

Also2 :
48/2(9+3) != 48/(2(9+3))
Now stop trolling, everything is clear.

[LT Profits]

Everyone who has just a little mathematical education knows that 48/2(9+3) is 288. There is no confusion here.
Ask some mathematicians.
LT Profits = go to the special olympics, you are a disgrace.

Also, if you are not sure about something mathematical, use this:

http://www.wolframalpha.com/input/?i=48%2F2%289%2B3%29

Also2 :
48/2(9+3) != 48/(2(9+3))
Now stop trolling, everything is clear.

Um,, excuse me!

The following makes it clear as day that the right answer is 2

"The general consensus among math people is that "multiplication by juxtaposition" indicates that the juxtaposed values must be multiplied together before processing other operations."

Thus, the 2(9+3) must be multiplied together before processing other operations. You are wight that there is no ambiguity here because I am right,

48/2(9+3) is NOT the same as 48/2*(9+3)

The former = 2 and the latter = 288, the reason being that there is no juxtaposition rule in the latter.

If you cannot see that, I don't know what to tell you.

[tenbas]

Um,, excuse me!

The following makes it clear as day that the right answer is 2

"The general consensus among math people is that "multiplication by juxtaposition" indicates that the juxtaposed values must be multiplied together before processing other operations."

Thus, the 2(9+3) must be multiplied together before processing other operations. You are wight that there is no ambiguity here because I am right,

48/2(9+3) is NOT the same as 48/2*(9+3)

The former = 2 and the latter = 288, the reason being that there is no juxtaposition rule in the latter.

If you cannot see that, I don't know what to tell you.

!= is the same as =/= or NOT THE SAME. So we agree here.

I really do not care for your rules. If a mathematician in any world country was given the 48/2(9+3) everybody would get same solution.
Of course, if you give the same sample on the net, people will come up with various crap.
The answer is 288. If I would write 48/2(9+3) = 2 on my exam, my professor would probably give me 1/10 just for that.

Now please stop telling me that 48/2(9+3) does not equal 288 because that is simply not true. If you can, however, mathematically proove me, please do so, I will study the proof and let you know what I think.

[Stinger]

I came out with 288 as well...

48/2(9+3)
48/2*12
24*12
288