[ 3 / biz / cgl / ck / diy / fa / ic / jp / lit / sci / vr / vt ] [ index / top / reports ] [ become a patron ] [ status ]
2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math

View post   
File: 7 KB, 251x251, 1279694680997s.jpg [View same] [iqdb] [saucenao] [google]
1451160 No.1451160 [Reply] [Original]

/sci/ I need your help, right now there's an argument on /b/ about a math problem. (the one in the picture)

Using PEMDAS I found it to be -18 but others are saying -4
because they said "when a problem is only addition and subtraction you go left to right and disregard PEMDAS" I have never heard of this, but I'm not going to say they're wrong since I don't know, I felt this was the right place to ask if they're right or not.

>> No.1451162

bump

>> No.1451171

It's -4

>> No.1451172

this is the thread in question /b/res/255142092#255157481

>> No.1451174

eleventeen

>> No.1451177

Saw this in /b/, PEDMAS.

1-12+7
1-19
-18

Have fun.

>> No.1451178

>>1451171
explain or you're trolling

>> No.1451181

>>1451177
>PEDMAS
lol wut?
>>1451174
gtfo /b/ I had a question for /sci/fags

>> No.1451185

1-3x4+7
1-12+7
-11+7
-4

>> No.1451186
File: 114 KB, 440x533, uupset.png [View same] [iqdb] [saucenao] [google]
1451186

>>1451181

>> No.1451191
File: 20 KB, 500x500, 1278990242359.png [View same] [iqdb] [saucenao] [google]
1451191

>>1451177
1-12+7
1-5

>> No.1451194

>>1451185
but you need to do addition first
>>1451186
I was, but that made me lol so I'm good now :3

>> No.1451195

1-3*4+7=
1-12+7=
-11+7=
92

>> No.1451200

>>1451195
...yes

>> No.1451230

>>1451200

I'm >>1451195

This is my first time on this board.
Do the elementary schoolfags often come here for someone to do their homework?

>> No.1451237

>>1451194
>but you need to do addition first

no, you dont, thats the problem with pedmas, you get the same result no matter if you do the addition or subtraction first

>> No.1451246

Parenthesis
Exponents
Multiplication
Division
Addition
Suptraction

>> No.1451247

1 - 3 x 4 + 7
(1 - 3) x (4 + 7)
(-2) x (11)
-4

>> No.1451256

http://www.algebrahelp.com/calculators/equation/calc.do?equation=1-3*4%2B7%3Dx&solvf=AUTO

>> No.1451259

Why PEMDAS? Because:
>Writing down operations without indicating the order to do them in is arbitrary.
>We made up an arbitrary but CONSISTENT order to do things in when someone is too dumb to indicate the order to do things in.
1-3*4+7
Parenthesis (None here)
Exponent (None here)
Multiply (Fuck yeah!)
1-(3*4)+7
1-12+7
Divide (None here)
Add (Hells yes)
1+(-12+7)
1+-5
1-5
Subtract (Finally, fuckin' A)
4

I used PARENTHESIS to indicate what order to do things in.

>> No.1451264

>>1451259
>4
Forgot your negative bro.
One little mistake and the whole thing is wrong.

>> No.1451275
File: 16 KB, 875x149, Untitled.png [View same] [iqdb] [saucenao] [google]
1451275

I used Google's search engine with it's built-in calculator, and got (-4). Here's the pic.

>> No.1451278

Order of Operations Trolling... good times man, good times.

>> No.1451306

>>1451264
An astronomer would call it great for being within an order of magnitude.

>> No.1451312

>>1451306
A physicist would be content it's not infinity.

>> No.1451339

>>1451312
A civil engineer would say "This needs units."

>> No.1451346 [DELETED] 

fucking 7th graders how do they work

the problem is 1-(3x4)+7
=
1-12+7+ -4

>> No.1451351

>>1451339
A philosophy major would shit his pants.

>> No.1451372

over 9k fu all

>> No.1451378

I'm pretty sure the OOO is everything in parentheses, then all exponents left to right, then multiplication & division left to right, then addition & subtraction left to right. M&D and A&S are done together, left to right, not separately.

Of course, I was taught this in one of the worst school districts in the country, so I figure anything I learned there is about as reliable as the Wikipedia.

>> No.1451381

>>1451275
You felt the need to 1) look it up and 2) screenshot to prove it? Seriously?

>> No.1451404

Let me explain some shit PEMDAS means PARENTHESES THEN EXPONENTS AND THEN ITS MULTIPLY AND DIVIDE AT THE SAME TIME FROM LEFT TO RIGHT SAME WITH ADDITION AND SUBTRACTION

>> No.1451407

>>1451177
after multiplication/division u just go from left to right
= -4

>> No.1451421

>>1451160

if its left to right when only addition and subtraction are left, then why the fuck would there be a AS at the end of PEMDAS? there would always only be addition and subtraction left eventually and that part could be discarded. FOLLOW PEMDAS ALWAYS

>> No.1451433

>>1451421
Addition is before subtraction in PEDMAS because that's the easiest way for kids to remember