48÷2(9+3) = ???? (material, websites, Opera, Google)

[ShadowCaver]

LOL - been following this thread since the beginning, off-and-on... my answer? "2"

Simply due to what I recall from my JHS & HS math courses many moons ago: "what is in parenthesis gets done first, followed by what is 'attached' to such, and then go left to right obeying the PEMDAS laws". Even from my BS degree in engineering, nothing swayed me from that process.

Funny,,, the other day, I asked oldest boy and some of his college freshman friends about this, and also the engineers that work for me: 6 out of 8 came back w/ the answer being "2", the other two [which was one from each group of people] replied with "288".

Main take-away that I see with this equation is that it has the potential to be ambiguous... that there are those that don't see the "2" as being tied-to what is w/in the parenthesis, but as tied-to 48. And IMHO, the former is the correct interpretation of this kind of equation. 6am more clearly lays this out in the above posts.

[gallowsCalibrator]

Originally Posted by 6am

Distributive property of multiplication states 2(9+3) cannot be separated.

Considering that the distributive property of multiplication is just multiplication and thus follows the order of operations (per the link I showed you, which even states that distribution occurs alongside division from left to right), can you provide evidence or proof to your statement?

Which is to say, provide a link.

Like this.

[PanTerra]

Here is a link. It might not be as pretty, and it isn't a blog.

//www.city-data.com/forum/19254043-post36.html

[gallowsCalibrator]

Originally Posted by PanTerra

Here is a link. It might not be as pretty, and it isn't a blog.

//www.city-data.com/forum/19254043-post36.html

> Implying that a post on City-Data without reference(s) has merit.

Several people have made claims regarding the obelus and distributive property of multiplication but yet to have provided sources.

Like this. (Notice the use of the obelus)

[prince40000]

Originally Posted by Charles

Saw this somewhere else. What is the answer? (There was no Math forum so I placed it here.)

man u guys are retarded, the answer is 2, whether u like it or not.

[Darkatt]

Originally Posted by Charles

Saw this somewhere else. What is the answer? (There was no Math forum so I placed it here.)

The answer is simple

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

24*12 = 288

http://knowyourmeme.com/memes/48293#.Tn_ZBGO_HZI

Why is there a question?

[PanTerra]

Originally Posted by Rita Mordio

> Implying that a post on City-Data without reference(s) has merit.

Several people have made claims regarding the obelus and distributive property of multiplication but yet to have provided sources.

Like this. (Notice the use of the obelus)

As much as a blog. Got to admit, they had pretty graphics. But it is still 2.

[Darkatt]

Originally Posted by PanTerra

As much as a blog. Got to admit, they had pretty graphics. But it is still 2.

Only if you cannot perform rudimentary math.

Since the multiplication and division are performed equally, (order of operation), the equation is performed from left to right.

Of course you can follow my resolution of the equation, or my link which tells you why it's actually 288, and the fallacy behind the answer 2.

Ask any decent Math teacher.

[PanTerra]

Originally Posted by Darkatt

Only if you cannot perform rudimentary math.

Since the multiplication and division are performed equally, (order of operation), the equation is performed from left to right.

Of course you can follow my resolution of the equation, or my link which tells you why it's actually 288, and the fallacy behind the answer 2.

Ask any decent Math teacher.

You don't know convention.

[rcsteiner]

Originally Posted by PanTerra

You don't know convention.

Actually, I think a classic infix to postfix conversion program (pushing operators and operands on a stack and popping them off in the correct order) would arrive at 288. Operations inside parenthesis are performed first as the closing paren is popped off the stack. Multiplication and division are equal in priority. Standard parsing and resolution is left to right.

It's an interesting puzzle, tho, and shows why ambiguity can cause issues for even "simple" problems.

Oh wait...

It's too late in the day. I punt. It might be 2. I need to write the code in several languages and see how they handle it.

The presence or absence of an implied multiplication is the turning point. I was always taught that a number adjacent to a right paren was implied multiplication, but a calculator generally needs explicit operators to be specified, so a lot will depend on how the parser is coded.