Nayos Posted April 10, 2011 Share Posted April 10, 2011 I looked back at your earlier posts, and agree with the interpretation offered by W|A. For the reasons I already stated earlier. You agree that they are different equations? Link to comment Share on other sites More sharing options...
Bengal34 Posted April 10, 2011 Share Posted April 10, 2011 You agree that they are different equations? You just multiplied by 1. It will not affect the end solution. The answer is 288. Link to comment Share on other sites More sharing options...
primexx Posted April 10, 2011 Share Posted April 10, 2011 You agree that they are different equations? sure. one is a / b while the other is a * b / c * d, of course they're different. Link to comment Share on other sites More sharing options...
Ambroos Posted April 10, 2011 Share Posted April 10, 2011 I looked back at your earlier posts, and agree with the interpretation offered by W|A. For the reasons I already stated earlier. http://mathforum.org/library/drmath/view/54342.html http://mathforum.org/library/drmath/view/57021.html back where we started. juxtaposition was never taught in any country where I've studied, but left-to-right in every one of them. edit: though certainly more parenthesis would be desirable in any serious context. Indeed. More parenthesis are needed. But when in doubt, I think you can say that multiplication indicated by juxtaposition is carried out before division. It's just the most consistent way of dealing with equitations, especially if you're also doing algebra (aka mathematics with symbols and not just numbers). So the conclusion on the original question stays: neither is correct, depending on what you consider conventional and what you learned, the conventional answer could be either 2 or 288. But neither is correct. Link to comment Share on other sites More sharing options...
primexx Posted April 10, 2011 Share Posted April 10, 2011 Indeed. More parenthesis are needed. But when in doubt, I think you can say that multiplication indicated by juxtaposition is carried out before division. It's just the most consistent way of dealing with equitations, especially if you're also doing algebra (aka mathematics with symbols and not just numbers). i think i've shown pretty conclusively that juxtaposition is a stupid rule to follow as an order of operation, as can been seen by nevann's biting the bullet on my example question. though i have no problem conceding that some people do use it, but i completely disagree with its use in this manner. Link to comment Share on other sites More sharing options...
Nayos Posted April 11, 2011 Share Posted April 11, 2011 i think i've shown pretty conclusively that juxtaposition is a stupid rule to follow as an order of operation, as can been seen by nevann's biting the bullet on my example question. though i have no problem conceding that some people do use it, but i completely disagree with its use in this manner. Your example question actually proved it. The juxtaposition of the 2 no longer applied in your second equation. Link to comment Share on other sites More sharing options...
RuudJacobs.NET Posted April 11, 2011 Share Posted April 11, 2011 Solve 48?2(9+3) 48/(18+6) = 48/24 = 2. Link to comment Share on other sites More sharing options...
Ambroos Posted April 11, 2011 Share Posted April 11, 2011 i think i've shown pretty conclusively that juxtaposition is a stupid rule to follow as an order of operation, as can been seen by nevann's biting the bullet on my example question. though i have no problem conceding that some people do use it, but i completely disagree with its use in this manner. If you mean this answer from nevann (https://www.neowin.net/forum/topic/989012-solve-48%c3%b7293/page__view__findpost__p__593875376), then nevann is completely correct if you take the juxtaposition convention into account. "Distributive multiplication implied by multiplication by juxtaposition" is just a combination of the fact that you do brackets before anything else, and "multiplication indicated by juxtaposition is carried out before division". Your example question actually proved it. The juxtaposition of the 2 no longer applied in your second equation. Indeed, we rock! Link to comment Share on other sites More sharing options...
Stetson Posted April 11, 2011 Share Posted April 11, 2011 Obviously the answer is 14. I can't believe how many of you fail at kindergarten calculus! Anyone who doesn't get 14 is wrong and stupid! <lack of explanation> :p Link to comment Share on other sites More sharing options...
Nayos Posted April 11, 2011 Share Posted April 11, 2011 Obviously the answer is 14. I can't believe how many of you fail at kindergarten calculus! Anyone who doesn't get 14 is wrong and stupid! <lack of explanation> :p Your logic is undeniable Link to comment Share on other sites More sharing options...
Gone Posted April 11, 2011 Share Posted April 11, 2011 Wow 13 pages of reply's on a math problem! Parenthesis Exponents Multiply Divide Add Subtract Solve 48?2(9+3): Parenthesis done first 48?2(12) now we multiply (2x12) 48?24 then we divided and get 2 :shifty: Link to comment Share on other sites More sharing options...
Nayos Posted April 11, 2011 Share Posted April 11, 2011 Wow 13 pages of reply's on a math problem! Parenthesis Exponents Multiply Divide Add Subtract Solve 48?2(9+3): Parenthesis done first 48?2(12) now we multiply (2x12) 48?24 then we divided and get 2 :shifty: 2 is correct but your reasoning isn't Link to comment Share on other sites More sharing options...
Dinggus Posted April 11, 2011 Share Posted April 11, 2011 PEMDAS.. 48/2(9+3) (9+3) = 12 2(12) = 24 48/24 = 2 so 48/2(9+3) = 2. Or the post above me, haha. Link to comment Share on other sites More sharing options...
Ambroos Posted April 11, 2011 Share Posted April 11, 2011 Wow 13 pages of reply's on a math problem! Parenthesis Exponents Multiply Divide Add Subtract Solve 48?2(9+3): Parenthesis done first 48?2(12) now we multiply (2x12) 48?24 then we divided and get 2 :shifty: Wrong again :p There is no rule as to whether you should do multiplication or division first, or adding and substracting. The correct order is: Parenthesis -> Exponents -> multiplicate/divide -> add/substract. Think again :p (answer is right though, as nevann said) Link to comment Share on other sites More sharing options...
Syanide Posted April 11, 2011 Share Posted April 11, 2011 First of all, people are confusing / with a fraction, which it is not, as you can even see from the post title, where OP used ?, it is a symbol for division and as such used only for the digit NEXT TO IT and just that one, not everything after it. It is the same as writing 1/2x and debating if it is 1 -- x 2 or 1 -- 2x because people left out any brackets to clear out confusion. If we follow the rule that / is just a division symbol (which any calculator ie your numpad does), which in this case IT ACTUALLY IS, not a straight line to cover everything after it as denominator, we get this 48 : 2 * (9+3) or to turn : into a properly formatted fraction 48 -- * (9+3) 2 CLEAR NOW? Ambroos logic is what's extremely annoying in this case, because he, along with majority of the people here, are making up brackets and not able to read the original formula... Link to comment Share on other sites More sharing options...
Gone Posted April 11, 2011 Share Posted April 11, 2011 2 is correct but your reasoning isn't The way I see it is, this is a good reason not to go to college!! Because no matter what, all the tens of thousands of dollars spent will prove that you may still be wrong, yet completely have a right answer, depending which method you use. Or at least remember pre-calc. Its the contradicting rules that make me have trouble with basic math problems, because I think to hard about it! And so I joined the military where I came across a problem like this, where I had to take a precision measurement on a jet engine component, and we (both my crew and the inspector) were coming up with two separate answers on what the result should be, because of PEMDAS. Needless to say, we agreed that since PEMDAS gave us a result closer to what we needed, we figured that we'd use it instead. I have yet to see that helicopter engine blow up. And therefore kids, you should Google search the other forums online arguing over this exact same math equation, as I just did. It is quite hilarious! Edit: I'll have to re-write this post in the morning, because now my head is spinning. Link to comment Share on other sites More sharing options...
Detection Posted April 11, 2011 Share Posted April 11, 2011 288? Following PEMDAS, I get 2: 48?2*(9+3) = 48?2*(12) = 48?24 = 2 The reason why some people are getting 288 is that they're forgetting that there's an invisible multiply sign in the expression. Honestly though, if I ever saw this I would apply a facepalm. It's not good notation and like you're seeing, it's ambiguous without proper use of parentheses and will confuse people. It's better notation to say LaTeX Code: \\frac{48}{2(9+3)} http://www.physicsforums.com/showthread.php?t=488334 Link to comment Share on other sites More sharing options...
primexx Posted April 11, 2011 Share Posted April 11, 2011 Your example question actually proved it. The juxtaposition of the 2 no longer applied in your second equation. If you mean this answer from nevann (https://www.neowin.net/forum/topic/989012-solve-48%c3%b7293/page__view__findpost__p__593875376), then nevann is completely correct if you take the juxtaposition convention into account. "Distributive multiplication implied by multiplication by juxtaposition" is just a combination of the fact that you do brackets before anything else, and "multiplication indicated by juxtaposition is carried out before division". to paraphrase what you guys just said: if you assume juxtaposition as a rule, then juxtaposition is correct. :rolleyes: I, for one, will not live in a world where multiplying an arbitrary term by 1 changes the answer. 288? Following PEMDAS, I get 2: 48?2*(9+3) = 48?2*(12) = 48?24 = 2 The reason why some people are getting 288 is that they're forgetting that there's an invisible multiply sign in the expression. Honestly though, if I ever saw this I would apply a facepalm. It's not good notation and like you're seeing, it's ambiguous without proper use of parentheses and will confuse people. It's better notation to say LaTeX Code: \\frac{48}{2(9+3)} http://www.physicsforums.com/showthread.php?t=488334 https://secure.wikimedia.org/wikipedia/en/wiki/Order_of_operation#Mnemonics Link to comment Share on other sites More sharing options...
Ambroos Posted April 11, 2011 Share Posted April 11, 2011 First of all, people are confusing / with a fraction, which it is not, as you can even see from the post title, where OP used ?, it is a symbol for division and as such used only for the digit NEXT TO IT and just that one, not everything after it. It is the same as writing 1/2x and debating if it is 1 -- x 2 or 1 -- 2x because people left out any brackets to clear out confusion. If we follow the rule that / is just a division symbol (which any calculator ie your numpad does), which in this case IT ACTUALLY IS, not a straight line to cover everything after it as denominator, we get this 48 : 2 * (9+3) or to turn : into a properly formatted fraction 48 -- * (9+3) 2 CLEAR NOW? Ambroos logic is what's extremely annoying in this case, because he, along with majority of the people here, are making up brackets and not able to read the original formula... Well damn, you are actually correct. Did some research and the obelus (?) is indeed different from a normal division (/) and applies only to the digit next to it. My humble apologies. In that case, the only possible correct answer is 288. However, 48/2(9+3) is still not mathematically possible, but depending on what conventions you are used to could be solved as either 2 or 288. No it's not, Googled some more. I can only conclude that mathematics suck, and if I'll ever have to solve something this unclear, I'll just ask for something more detailed. Link to comment Share on other sites More sharing options...
Nayos Posted April 11, 2011 Share Posted April 11, 2011 288? Following PEMDAS, I get 2: 48?2*(9+3) = 48?2*(12) = 48?24 = 2 The reason why some people are getting 288 is that they're forgetting that there's an invisible multiply sign in the expression. Honestly though, if I ever saw this I would apply a facepalm. It's not good notation and like you're seeing, it's ambiguous without proper use of parentheses and will confuse people. It's better notation to say LaTeX Code: \\frac{48}{2(9+3)} http://www.physicsforums.com/showthread.php?t=488334 Well, actually once you get to 48?2*(12) the answer is 288 This is because the multiplication doesn't come before division (nor vice versa). 48?2*(12) can be re-written as 48*(1/2)*12 which is 288 The reason some of us get 2 is because of multiplication by juxtaposition. This states that the 2(9+3) should be done before any remaining multiplication or division (in this case 48/(24)). However, some people don't agree with the juxtaposition-rule-thing. That's why we have different answers. Link to comment Share on other sites More sharing options...
primexx Posted April 11, 2011 Share Posted April 11, 2011 Well damn, you are actually correct. Did some research and the obelus (?) is indeed different from a normal division (/) and applies only to the digit next to it. My humble apologies. In that case, the only possible correct answer is 288. However, 48/2(9+3) is still not mathematically possible, but depending on what conventions you are used to could be solved as either 2 or 288. wait, what? okay i'm lost now. edit: saw your edit. Link to comment Share on other sites More sharing options...
Detection Posted April 11, 2011 Share Posted April 11, 2011 The meaning of life, the universe, and everything is 42 Link to comment Share on other sites More sharing options...
Nayos Posted April 11, 2011 Share Posted April 11, 2011 Well damn, you are actually correct. Did some research and the obelus (?) is indeed different from a normal division (/) and applies only to the digit next to it. My humble apologies. In that case, the only possible correct answer is 288. However, 48/2(9+3) is still not mathematically possible, but depending on what conventions you are used to could be solved as either 2 or 288. Even if the obelus only applies to the digit next to it, does that even matter if we're using the juxtaposition rule? Wouldn't that still come before the obelus operation? Nevermind, saw your edit. Link to comment Share on other sites More sharing options...
qdave Posted April 11, 2011 Share Posted April 11, 2011 This thread shows that computer science degree is useless :D Link to comment Share on other sites More sharing options...
Ambroos Posted April 11, 2011 Share Posted April 11, 2011 My previous answer about conventions and the mathematical incorrectness of the equitation still stands. What Syanide said about the obelus (?) versus the forward slash (/) is invalid. Obelus means division. Forward slash means division. Exactly the same thing. Link to comment Share on other sites More sharing options...
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