EPTUniversity of Ottawa, Telfer School of Management.
Although I don't know what that has to do with anything... many other posters have talked about how their universities put multiplication by juxtaposition at a higher priority...
A Simple Math Problem? - Page 90
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Insanious
Canada1251 Posts
University of Ottawa, Telfer School of Management. Although I don't know what that has to do with anything... many other posters have talked about how their universities put multiplication by juxtaposition at a higher priority... | ||
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FindMeInKenya
United States797 Posts
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gerundium
Netherlands786 Posts
On April 09 2011 10:04 FindMeInKenya wrote: Again, read that long post on page 62, which basically explains why there's no priorities for real numbers. Maybe your Uni and work has some rules for the sake of simplification, but for a theoretical mathematician, 288 is the only agreeable answer. how about no. A mathematician would see that the question is phrased poorly and whoever did it has failed to make his intentions clear, therefor arguing any side is pointless. | ||
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yellowmoe
Canada59 Posts
On April 09 2011 09:07 tpir wrote: Just to make things confusing not all calculators do it the same! (Credit to econ and dukemagic at twoplustwo for these links!) Pic of TI-85 vs. TI-86: http://img339.imageshack.us/img339/9549/headasplode.jpg Screen grab of pertinent order of operations section: http://i.imgur.com/aP7Gg.jpg Source: http://math.ucsd.edu/~ashenk/Calculators/Getting_Started_TI-86.pdf holy crap, I just wanted to to say, I didn't know they made TI calculators into the 86. I still use the TI-83. I am studying engineering and I chose 2, is this bad? | ||
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FindMeInKenya
United States797 Posts
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gerundium
Netherlands786 Posts
On April 09 2011 10:08 FindMeInKenya wrote: i'm not arguing that the question is phrased poorly, but if we look it as is, the answer is 288. so you claim that there is no ambiguity? and sticking to it? I am done in this thread i guess, it's starting to feel like a religious argument. both sides keep arguing over something without any real claims to back up either side and not changing positions in the slightest. | ||
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Leath
Canada1724 Posts
But then I realized it was the wrong answer. Obviously you treat whatever is inside the parenthesis first, so, 48÷2 (12) = But now you have the same as: 48 ÷ 2 × 12 And the way to solve is from left to right, so, 24 × 12 = 488 It is so tempting however to solve the whole 2(9+3) first and obtain 24. I guess it does depend on the system, like others have mentioned. Some system place priorities on the multiplication sign over the division. | ||
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Ace
United States16096 Posts
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L3gendary
Canada1470 Posts
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DragonDefonce
United States790 Posts
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DiamondTear
Finland165 Posts
 I see 1/2 as ½. So my answer would be 0.5x. However, if the problem was 2/4x, I might go for the 2 divided by 4x train of thought which seems to be the favorite amongst TL users. When I was in starting learning algebra I actually had a lot of trouble with this because in grades 3-6 we could use either fractions or : to mark dividing. I used : because it was neater so I had to get used to using fractions later. I wish no one was taught"÷". On April 09 2011 09:07 tpir wrote: Just to make things confusing not all calculators do it the same! (Credit to econ and dukemagic at twoplustwo for these links!) Pic of TI-85 vs. TI-86: http://img339.imageshack.us/img339/9549/headasplode.jpg Screen grab of pertinent order of operations section: http://i.imgur.com/aP7Gg.jpg Source: http://math.ucsd.edu/~ashenk/Calculators/Getting_Started_TI-86.pdf Always be careful when using a calculator. I usually use extra parentheses to make sure I get the correct result. Casio FX 1.0 PLUS gives the result 2. I'm a bit shocked by this because I've been using this calculator for 8 years and I assumed the result would be the correct 288. It would seem that the calculator considers 2(9+3) to be the denominator but if you input it as 2*(9+3) it's calculated correctly with only 2 as the denominator. I think this is retarded. Another option is to use the fraction button instead of the divide button. When input like this, the result is the correct 288. I suspect this is the case with http://img19.imageshack.us/img19/6273/ducy.jpg, only with the problem that you can't see that he used a different button (unlike with my Casio). | ||
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Severedevil
United States4839 Posts
On April 09 2011 10:04 FindMeInKenya wrote: Again, read that long post on page 62, which basically explains why there's no priorities for real numbers. Maybe your Uni and work has some rules for the sake of simplification, but for a theoretical mathematician, 288 is the only agreeable answer. No. You are ignorant, and willfully so, and in your false invocation of authority, you may mislead others. There are multiple conflicting 'standard' conventions for parsing the sequence of symbols depicted. In one of them, multiplication by juxtaposition takes precedence over multiplication/division by explicit symbol. In the other (of the ones we're considering), it does not. | ||
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hifriend
China7935 Posts
On April 09 2011 10:18 L3gendary wrote: I'm quite saddened 44% of people actually think it's 2. The problem is just set up in a way so that a large amount of people are bound to misinterpret it. Doesn't necessarily mean they are worse at algebra than the other 56%. | ||
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fishball232
United States90 Posts
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RevLesMis
United States23 Posts
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reprise
Canada316 Posts
On April 09 2011 10:42 RevLesMis wrote: i dont get this shit ive always been told it was PEMDAS why is it just in order? where are you guys getting this? PEMDAS is not the end-all-be-all answer. It is an elementary tool used to teach order of operations, but shouldn't be referenced upon as complete proof. Read the last couple pages and you'll see where the argument stands, which is whether or not multiplication by juxtaposition has priority. | ||
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Rtran10
Canada78 Posts
http://mathforum.org/library/drmath/view/54341.html | ||
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quiggy
Canada58 Posts
1-1+1-1+1-1 . . . =1 0=1 /this thread | ||
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Wonderballs
Canada253 Posts
If you don't define the problem accurately, some people can fumble through it; But you're the moron who can't spell. Is this a good analogy? | ||
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fishball232
United States90 Posts
1-1+1-1+1-1 . . .=0 1-1+1-1+1-1 . . . =1 0=1 /this thread you are adding a one more term, you get 1 or 0. essentially it'd the difference between the number of terms you have. this is a geometric series where r=-1 so it diverges. no answer so 0=/1 calculate this 1+1/2+1/4+1/8+1/16..... | ||
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