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/sci/ - Science & Math

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2961847

REQUEST STICKY grey !bEke8twiXQ Thu Apr 28 17:20:52 2011 No.2961847 [Reply] [Original]

To all of you who are having trouble with the following problem: 6÷2(1+2)

Here is the answer.
Yes. It equals 9. Deal with it.

This is why:
Order of Operations states that when there is both multiplication and division present, you must work from left to right. Apparently, our math teachers have failed to do their job. For more information about PEMDAS, visit this link:
http://www.purplemath.com/modules/orderops.htm

Now then, I will solve the problem for you.
Here is our original: 6÷2(1+2)
Order of operations states we perform whatever operation is within the parenthesis first, which in this case, is 1+2.

Now we have 6÷2(3)

Here is where many go wrong. They seem to want to multiply 2 by 3, which leaves you with 6÷6=1. BUT, since there is multiplication AND division present, we work from left to right. If it makes it any easier, think of the problem like this: 6÷2•3

Now, we divide 6 by 2, giving us 3. Here is our problem now:
3(3)=9

TA DAA

Now that we all know how it works, let us never speak of this again. Any troll who persists and continues to ask about this problem can kindly go swallow a fork.

>>	Anonymous Thu Apr 28 17:22:52 2011 No.2961867 File: 2 KB, 92x83, imagess.jpg [View same] [iqdb] [saucenao] [google] Please tell me this is a joke.

>>	Anonymous Thu Apr 28 17:24:52 2011 No.2961876 File: 117 KB, 493x375, 1297739883374.jpg [View same] [iqdb] [saucenao] [google] bumping for sticky. 'Bout time

>>	Anonymous Thu Apr 28 17:27:52 2011 No.2961905 Nobody has trouble with it except for retards on facebook and trolls.

>>	Anonymous Thu Apr 28 17:39:52 2011 No.2961970 >>2961905 this and using inline division (÷) should be punishable by death

>>

Anonymous Thu Apr 28 17:46:52 2011 No.2962024

>>2961847
>we work from left to right

Why ?
I can do whatever I want, since if you have a doubt you can just go and check the previous line of calculation.
If you are to write down ambigious expressions it is your fault that you get 2 kinds of answers.

>>	Anonymous Thu Apr 28 18:10:52 2011 No.2962161 Depends on the country you learned maths. Britfags learn that division takes priority

>>	Anonymous Thu Apr 28 18:16:52 2011 No.2962181 I define the answer to be 42 why? Because I fucking say so and I am boss and there's no fucking thing you can do about it

>>	Anonymous Thu Apr 28 20:27:52 2011 No.2962884 >>2962024 it makes it so it's clear what the original writer meant so dumbfucks like you can't use the 'DERP I CAN DO WHATEVER I WANT AND GET A DIFF ANSWER'.

>>	Anonymous Thu Apr 28 20:38:52 2011 No.2962934 >>2961847 Here's where you went wrong op. You assumed that: 6÷2(1+2)=(6÷2)(1+2) Rather than: 6÷(2(1+2)) You should not assume this.

>>	‮‬ !.OPIsFAG5Y Thu Apr 28 20:39:52 2011 No.2962942 You're all wrong. It's 288.

>>	Anonymous Thu Apr 28 20:40:52 2011 No.2962952 >>2962942 >Long ago, in an equation far... far away...

>>	Anonymous Thu Apr 28 20:42:52 2011 No.2962961 >>2962934 Here's where you went wrong You assumed that: 6÷2(1+2)=6÷(2(1+2)) Rather than: (6÷2)(1+2) You should not assume this.

>>	Anonymous Thu Apr 28 20:44:52 2011 No.2962975 Always do parenthesis first 6/2(1+2) 2(3) 6 6/6 1 It is not (6/2)x(1+2)

>>	‮‬ !.OPIsFAG5Y Thu Apr 28 20:44:52 2011 No.2962983 >>2962961 >>2962934 Protip: There's no place for implied parenthesis outside of calculator programming. <span class="math">÷2 = *2^{-1}[/spoiler]

>>	Anonymous Thu Apr 28 20:44:52 2011 No.2962974 >>2962961 You should assume neither.

>>	Anonymous Thu Apr 28 20:45:52 2011 No.2962988 >>2962975 >It is not (6/2)x(1+2) Why not?

>>	Anonymous Thu Apr 28 20:46:52 2011 No.2962995 >>2962974 Right, so follow the order of operations. 6/2x(1+2) Even though the "x" isn't there, it's implied. From left to right now (because M and D have equal priority, hey that rhymes). 6/2 = 3 3(1+2) = 9

>>	Anonymous Thu Apr 28 20:46:52 2011 No.2962996 >>2962975 6/2(1+2) 6/23 3*3 9

>>	Anonymous Thu Apr 28 20:47:52 2011 No.2962998 >>2962975 hi thar. the 2 isn't in the paranthesis. also for the OP, you can do it right to left or up or down, it doesn't matter at all.

>>	Anonymous Thu Apr 28 20:49:52 2011 No.2963006 >>2962975 6/2 is definitely 2. Keep doing math, and keep the faith alive.

>>	Anonymous Thu Apr 28 20:50:52 2011 No.2963010 6÷2(1+2) 2•1 = 2 2•2 = 4 6÷2+4 3+4 7 Deal with it.

>>	Anonymous Thu Apr 28 20:53:52 2011 No.2963030 If someone hands you an equation with implied order of operation, they're either inept or trolling, and you correct or ignore them as needed. End of fucking story.

>>

Anonymous Thu Apr 28 20:54:52 2011 No.2963034

Example 1.

6
-- (1+2) = (6÷2)(1+2)
2

Example 2.

6
--------- = 6÷(2(1+2))
2(1+2)

Your use of the order of operations still assumes that the question is in the form of my first example. When you can easily apply the order of operations to both.

The question is ambiguous because it does not tell you which form it is in.

>>	Anonymous Thu Apr 28 20:55:52 2011 No.2963046 6/2(1+2) 6/23 31/23 =4,5 deal with it faggots!

>>	Anonymous Thu Apr 28 20:55:52 2011 No.2963044 >>2963034 Just an example of how the linear method of writing formulae is flawed.

>>	Anonymous Thu Apr 28 21:01:52 2011 No.2963072 >>2963006 >6/2 is definitely 2. Not sure if trolling or very stupid

>>

Anonymous Thu Apr 28 21:02:52 2011 No.2963081

>>2963034
no, you assume nothing when doing it as per 1). if you do 2) you assume a non-existent paranthesis.
1) does not require paranthesis between the 6 and 2 because the order of doing linear equations works as though it was there.
6/2*4/9 is just that, and is not in any way ambiguous unless you can't read linear.

>>	Anonymous Thu Apr 28 21:02:52 2011 No.2963082 >>2961847 Anyone else realize that this is the entire reason latex exists? Perpetuating this shit just makes you stupid.

>>	Anonymous Thu Apr 28 21:02:52 2011 No.2963084 Fuck this shit, everyone asking this is a highschooler who saw the facebook quiz and wants to answer it.

>>	Anonymous Thu Apr 28 21:10:52 2011 No.2963126 >>2963081 6 --------- = 6/2(1+2) 2(1+2) No assumed parentheses there.

>>	Anonymous Thu Apr 28 21:13:52 2011 No.2963140 >>2963126 you fucking wrote the linear in your post. bad troll or completely retarded you are padawan.

>>

Anonymous Thu Apr 28 21:17:52 2011 No.2963156

>>2963140
I assume you're talking about this post

>>2963034
Where I wrote
6
--------- = 6÷(2(1+2))
2(1+2)

You're saying I put non-existent parentheses there correct?

I only did that to clarify how people are reading the different form of writing an ambiguous question.

In >>2963126
I returned to writing the equation in its original, ambiguous form.

>>	Anonymous Thu Apr 28 21:18:52 2011 No.2963159 However 1/2x is not x/2. >Why not? >ur not following pedmas. >im op and im a faggot Because its an algebraic agreement. (just read any math book) answer could be both 1 and 9. And its not a math problem. Its just a conception one.

>>	Anonymous Thu Apr 28 21:20:52 2011 No.2963174 It honestly doesn't matter what order this is done in, the answer will be 9. 6/2(1+2) 6/2(3) (6/1)(1/2)(3/1) (18/2) 9

>>	Anonymous Thu Apr 28 21:22:52 2011 No.2963184 6/2(1+2) 6=x 2(1+2)=y x/y = 1

>>

Anonymous Thu Apr 28 21:25:52 2011 No.2963198

>>2963156
>>2963126
ok utterly retarded it is.

yes there is. else it would be 6/(2(1+2))
writing 6/2(1+2) in linear can mean ONE thing and one thing only. 6 divided by 2 times 3. anything else you feel like doing is assuming non-existent paranthesis, as in >>2963126
those are not and will never be equal.

>>	Anonymous Thu Apr 28 21:28:52 2011 No.2963216 File: 12 KB, 240x332, Alfred_Tarski.jpg [View same] [iqdb] [saucenao] [google] This thread is now about making Polish Notation the standard.

>>	Anonymous Thu Apr 28 21:29:52 2011 No.2963218 >>2963198 Give me mathematical proof, not assertions. 6 divided by 2 times 3. Is that: 6 divided by 2, times 3 or 6, divided by 2 times 3 ? >those are and will never be equal Because your willpower makes it so?

>>	Anonymous Thu Apr 28 21:29:52 2011 No.2963221 >>2963216 So what is 6\3*2 ?

>>

Anonymous Thu Apr 28 21:35:52 2011 No.2963255

>>2963218
there is no mathematical proof for reading linear left to right, just as there is none for reading text left to right.
I bet you can find a written ISO standard if you feel you need to.

standard linear equations always go left to right, and in normal order or operation. if you want to create your own way of interpreting standard linear equations feel free.
for the rest of the world it doesn't make the equation any more ambiguous though.

>>	Anonymous Thu Apr 28 21:36:52 2011 No.2963260 >>2963255 Its called an axiom. Its the basic reason math exists in the first place.

>>	Anonymous Thu Apr 28 21:37:12 2011 No.2963266 File: 6 KB, 450x190, reta.png [View same] [iqdb] [saucenao] [google] Can someone give me a hand? I know both of them are parallel but i cant find the distance between them :/

>>	Anonymous Thu Apr 28 21:44:52 2011 No.2963309 >>2963255 Try something for me will you? Write 6/2(1+2) in a non linear format. Like this: x -- y Tell me why you do it as you do.

>>	Anonymous Thu Apr 28 21:56:52 2011 No.2963381 Hi Joe, It's over 9000!

>>	Anonymous Thu Apr 28 22:01:52 2011 No.2963422 This thread is why I don't fucking understand postfix expressions aren't taught in school

>>	Anonymous Fri Apr 29 06:57:52 2011 No.2965308 >>2963422 >postfix expressions What's that?

>>	sage sage Fri Apr 29 06:59:52 2011 No.2965313 File: 20 KB, 320x240, 1296136075198.jpg [View same] [iqdb] [saucenao] [google] >>2961847 0/10000000

>>	Anonymous Fri Apr 29 07:04:52 2011 No.2965319 Or you just rewrite division as multiplication. 6÷2(1+2) = 6(1/2)(3) = 33 = 9 = 61.5 = 9 It's just trolling, really.

>>	Anonymous Fri Apr 29 07:14:52 2011 No.2965342 >>2965319 Or you just rewrite division as multiplication. 6÷2(1+2) = 6(1/2)(3)^(-1) = 6*6^(-1) = 1 It's just trolling, really.