Simple Maths

  On 4/9/2011 at 7:58 PM, ZiggomaticV17 said:

Three sailors decided to share a motel room for $30 a night or $10 each. After they've checked in the manager feels guilty for charging so much, so he gives the bellhop $5 to take to the sailors. The porter is mad at the sailors for not tipping him, so he keeps $2 and gives each man $1.

 

Each sailor now has paid $10 - $1 = $9. $9 x 3 = $27. Add the $2 the bellhop kept and we have $29. Where is the other dollar?

 

No Cheating now.

that's a weird question and i've seen it before but don't recall the actual answer that was given..

here's how i did it:

start with each man's 10 bucks. multiply by 3. 30 bucks was the price.

take away five bucks. the price is now 25 bucks.

each sailer gets a dollar back.

the price they collectively paid is now 28 bucks.

divide that by 3, you get $9.33 per person.

the dude kept 2.

28 + 2 = $30

lol using wolframalpha with an ALTERED formulation to prove your point (i don't remember there being a "*" initially).

even like this 48/2(9+3) (with a "/" instead of a lame "÷") it would still be 2.

48

_____ is obviously 2

2(9+3)

like this , or like this 48/2*(9+3), or like this 48÷2*(9+3) it would be 288, yes. but if that were the original formulation, there wouldn't be any confusion.

I'm guessing this is a silly chain-mail "brainteaser" thing that's made its way onto watmm, and whose answer is obviously (cough cough) 288 but it's suppose to trick you that it's 2. Problem is, while the formulation is a bit needlessly ambiguous, it's not quite deceptive enough that, if you know your shit, it ISN'T 2. If the brainteaser starts with the premise that THAT formulation equals 288, it's flawed from the get-go. it needs a "*", otherwise the parentheses'd addition is solved first, and the multiplication of that addition is done as the second operation if the number simply prefaces the parentheses without any symbol in between, with the division being done as the last operation.

at least, that's what we're taught 'round these parts. :sup:

I really appreciated your help about my rectangle dilemma guys, but i'm having another one

is there a struct/object in obj-c that can represent a line (segment) and more importantly tell if another line (segment) intersects it ?

I saw there is the NSBezierPath class. You can define it with lines, but that seems to be a little overkill for what i'm trying to do.

Or should I implement a few methods/functions on the basis of what i learn about lines in highschool ?

fart.

thanks.

no idea bababrababrr maybe set up the geometric equations of the lines and solve them?

  On 4/9/2011 at 8:08 PM, Lube Saibot said:

lol using wolframalpha with an ALTERED formulation to prove your point (i don't remember there being a "*" initially).

 

even like this 48/2(9+3) (with a "/" instead of a lame "÷") it would still be 2.

 

48

_____ is obviously 2

 

2(9+3)

 

like this , or like this 48/2*(9+3), or like this 48÷2*(9+3) it would be 288, yes. but if that were the original formulation, there wouldn't be any confusion.

 

I'm guessing this is a silly chain-mail "brainteaser" thing that's made its way onto watmm, and whose answer is obviously (cough cough) 288 but it's suppose to trick you that it's 2. Problem is, while the formulation is a bit needlessly ambiguous, it's not quite deceptive enough that, if you know your shit, it ISN'T 2. If the brainteaser starts with the premise that THAT formulation equals 288, it's flawed from the get-go. it needs a "*", otherwise the parentheses'd addition is solved first, and the multiplication of that addition is done as the second operation if the number simply prefaces the parentheses without any symbol in between, with the division being done as the last operation.

 

at least, that's what we're taught 'round these parts. :sup:

i'vr nrever seen a * in these thigns. the parenthesis act the same way. solve the addition and then solve left to right.

but you've seen ÷ plenty of times, right?

the whole point of not using a multiplication sign is to think of the factors as one quantity.

() is a multiplication sign though (unless separated from the surrounding terms by another operator like + or -)

gnome sane

no?

  On 4/9/2011 at 8:55 PM, luke viia said:

() is a multiplication sign though (unless separated from the surrounding terms by another operator like + or -)

 

gnome sane

yeah.

  On 4/9/2011 at 8:55 PM, GORDO said:

no?

http://zonalandeducation.com/mmts/expressions/notesAboutMultAndDiv.html

the whole "controversy" is over whethere adjacency between two numbers implies that their evaluation take precedence in the order of operations, as well as confusion over the division symbol's meaning. is 4 blah!bn9pguaer

  On 4/9/2011 at 9:08 PM, luke viia said:

  On 4/9/2011 at 8:55 PM, GORDO said:

no?

 

http://zonalandeducation.com/mmts/expressions/notesAboutMultAndDiv.html

() is a separator, () does not mean multiplication, juxtaposition means multiplication, juxtaposition is not a symbol.

() does indeed mean multiplication when the only terms involved are numbers. if there were variables involved, it would be different and i would agree with you. the original question that disp posted has no variables.

I'm by no means a genius, but the way I was taught, it's 2.

  On 4/9/2011 at 9:22 PM, luke viia said:

() does indeed mean multiplication when the only terms involved are numbers. if there were variables involved, it would be different and i would agree with you. the original question that disp posted has no variables.

sigh... when there are numbers involved () are used to SEPARATE them, so that multiplication can be read from it (juxtaposed symbols are factors in a multiplication operation). the symbol doesn't mean multiplication, the syntax implies it. but whatever... it's not really important.

how is there a two-page thread about this in fifty posts per page view

you do the shit in brackets first

they teach you this in primary school

  On 4/10/2011 at 4:25 AM, kaini said:

how is there a two-page thread about this in fifty posts per page view

 

you do the shit in brackets first

 

they teach you this in primary school

WATMM, bro.

its MATHS you guys

dont forget the S

u dummies

Honestly, just don't use the fucking division symbol (÷). I haven't used that shit in many years. Do what Wolfram Alpha does.

Or just make it fucking explicit with more parenthesis: (48 ÷ 2) (9 + 3) = 288

For any practical application you'll know what order to do them in, so it won't ever be a real problem unless you give it to someone else and don't tell them what each of the numbers represent. If it's just arbitrary numbers you're throwing together in an arbitrary way, whoopdee doo. Just be more explicit or something.

  On 4/10/2011 at 7:17 AM, chenGOD said:

  On 4/10/2011 at 4:25 AM, kaini said:

how is there a two-page thread about this in fifty posts per page view

 

you do the shit in brackets first

 

they teach you this in primary school

 

WATMM, bro.

To be fair, the forums I've seen this on it has spiraled out to be tens of pages. It's serious business.

288, bitches

2 actually. Brackets have priority, so any number associated directly to it gets involved with it. This way it's 48: (2x12)=2 Isn't this one of the biggest points of brackets?

There should be no difference if you start at left or right as you have to multiply and devide first anyway, and then it doesn't matter anymore if you start adding or subtracting from left or right.

the only association that counts regarding the brackets is the stuff that's inside the brackets. because almost the entire discussion is about this point i'd like to see sources saying otherwise. as far as i know, there's no special rule for distributive properties. if there is, please point to a source that says that distributive properties should be calculated before normal multiplications/divisions.

or keep on trolling. that's fine too.

*has another ruff sunday morning*

just stopping by this thread to say,

what sort of sad excuse for a person would forget PEMDAS?

normally trolls claiming to have some higher knowledge of mathS that's beyond the pemdas. probably some sort of stoner high with an MIT degree on trolling.