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munchmunch
Canada789 Posts
On April 08 2011 07:25 YokaY wrote: Your math program just doesn't accept any part of the problem if theres no operator. Nope, it's actually something else, see my post above. You can actually write 2(3+5) in maple, and it will always evaluate to 2. Replace 3+5 with any expression, and 2 will still be returned. | ||
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GizmoPT
Portugal3040 Posts
On April 08 2011 07:24 koreasilver wrote: lol you failed with the troll because the 2 in the front and the 2 in the back cancel out each other.  i know lololol that was the joke... :\ | ||
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Twistacles
Canada1327 Posts
1 --- 2x no? | ||
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RoyalCheese
Czech Republic745 Posts
On April 08 2011 07:24 munchmunch wrote: Woah, what fucked up version of maple is that??? Ok, I just did some experiments, and I realized what is going on there. Maple should really be giving an error, but it is actually evaluating 48 / 2 to 24, and then treating 24 as a function. You see, 24 is the function that returns 24 on all arguments. Weird... yeah i think so. It probably means that the original problem wasn't correctly formulated  | ||
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Mailing
United States3087 Posts
On April 08 2011 07:23 koreasilver wrote: What they're saying is that technically this is wrong because technically 48÷2(12) is no different from 48 ÷ 2 x 12. But in our mathematics classes it has always been that we would interpret the notation as you have, and that this was just a given. So in conventional use it would be 2, but technically it is 288. I learned that it is mathematical law(?) that you distribute always after parenthesis 48÷2(9+3) is essentially 48 / (18 + 6), but it is far more simple to do 48÷2(12) first THEN distribute to 48÷24 The other way people have been getting 288 is just mathematically incorrect, regardless of interpretation, from what I learned.... Am I wrong or does everywhere else teach math wrong? o_0 | ||
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Retgery
Canada1229 Posts
I am not aware of any difference between / and the other division sign... they both mean the same thing to me. Can anyone point me to a reference that says otherwise? When multiplying fractions the basic rule comes to something like this; a/b * c/d = ac/bd Some people see this question as 48/2 (a fraction) multiplied by (9+3)/1 which in turn = 48(9+3)/2, which equals 288 Others see it as 48 ÷ 2(9+3) (not a fraction) and use BEDMAS or PEDMAS to solve the question which = 2 I saw the second scenario before the first because my calculator has both the "/" and the "÷" symbols. (Should I post a picture of my calculator with both answers?) | ||
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Raiznhell
Canada786 Posts
48/2(9+3) obviously you do Brackets first so: 48/2(12) which is basically 48÷2x12. Now Solving the Equation from LEFT to RIGHT it goes 48÷2 first which is 24 so: 24x12 which equals 288. Yeah I feel kinda noobish for mistaking it for 2 off just looking at it but I think it's a very easy mistake for anyone to make especially if you haven't been around math in awhile. | ||
micronesia
United States24772 Posts
On April 08 2011 07:26 Twistacles wrote: For the x...aren't both right? I mean, depending on how it's written on paper, it can either be .5X or 1 --- 2x no? Technically 1/2x means 1 divided by 2, and then everything times x. In practice, people usually mean 1/(2x). Both are not technically correct. Either one could be intended if you see it written that way, but usually the latter. Thus, it is effectively ambiguous even though it is technically correct. | ||
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darmousseh
United States3437 Posts
On April 08 2011 07:24 munchmunch wrote: Woah, what fucked up version of maple is that??? Ok, I just did some experiments, and I realized what is going on there. Maple should really be giving an error, but it is actually evaluating 48 / 2 to 24, and then treating 24 as a function. You see, 24 is the function that returns 24 on all arguments. Weird... Maple assumes that if you don't write the operator, then you want to multiply those parameters. In maple 24/12*(9+3) means (24/12)*(9+3) 24/12(9+3) means (24)/(12*(9+3)) it's this way because humans mistakingly write 1/(2x) as 1/2x. Maple assumes that all humans make this mistake and thus interprets it this way. | ||
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mprs
Canada2933 Posts
On April 08 2011 07:21 RoyalCheese wrote: I made a couple of experiments in the Maple (math software we use) and there are some interesting results. Perheps there should have been a 24 option in the pool :D + Show Spoiler + Darn you, I was just about to point this out <3 Maple As a math minor, I am somewhat in a position to comment. Once you get past high school maths (and to a sense, first year university), calculations become less and less frequent. Furthermore, most of the people at my University adopted the semantics (maybe the wrong word) of the first few professors we had. As such, as long as it is clear and unambiguous, then it should be fine. Like the OP says, does 1/2x become (1/2)*x or 1/(2*x). In this case, I would certainly say 1/(2x) because thats what the conventions (omg this is the word i was looking for!) that I've used for like 6 years. If this was 1/2*12, I would refer back to my grade school math classes and say the other way. Either way, it really is a matter of convention. Furthermore, the way the question is posed in the OP is incorrect and very ambiguous. A great illustration as to why brackets are our friends! | ||
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Deja Thoris
South Africa646 Posts
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Pufftrees
2449 Posts
Lol how are there 21 pages "debating" and explaining? It's MATH, that was done a lonngggg time ago for us. | ||
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GizmoPT
Portugal3040 Posts
On April 08 2011 07:27 Retgery wrote: When multiplying fractions the basic rule comes to something like this; a/b * c/d = ac/bd Some people see this question as 48/2 (a fraction) multiplied by (9+3) which in turn = 48(9+3)/2, which equals 288 Others see it as 48 ÷ 2(9+3) (not a fraction) and use BEDMAS or PEDMAS to solve the question which = 2 I saw the second scenario before the first because my calculator has both the "/" and the "÷" symbols. (Should I post a picture of my calculator with both answers?) i love u | ||
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koreasilver
9109 Posts
I realized and edited in my realization too late. I'll just excuse myself. | ||
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snow2.0
Germany2073 Posts
srsly, math without formatting isn't math. do it proper or dont do it. Anyone answering the question in a serious setting is taking a gamble with the questioneer being lazy while typing this out. | ||
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FiWiFaKi
Canada9859 Posts
On April 08 2011 07:26 Mailing wrote: I learned that it is mathematical law(?) that you distribute always after parenthesis 48÷2(9+3) is essentially 48 / (18 + 6), but it is far more simple to do 48÷2(12) first THEN distribute to 48÷24 The other way people have been getting 288 is just mathematically incorrect, regardless of interpretation, from what I learned.... Am I wrong or does everywhere else teach math wrong? o_0 Brackets Exponents Division Multiply Add Substract You wont get it wrong if you do it like that.... | ||
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micronesia
United States24772 Posts
On April 08 2011 07:28 Pufftrees wrote: I love watching people fumble over math, does that make me a bad person? Lol how are there 21 pages "debating" and explaining? It's MATH, that was done a lonngggg time ago for us. Maybe because most of it is not spent discussing which answer is correct? Well a lot of it is, and that's mostly because people don't read the darn thread, but a lot of it is spent discussing other things that you seem to have missed. | ||
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Torte de Lini
Germany38463 Posts
Here you go, this should help solve issues. Do what's on the inside first (9+3) then (48/2) then multiply. | ||
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emythrel
United Kingdom2599 Posts
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Myles
United States5162 Posts
On April 08 2011 07:26 Mailing wrote: I learned that it is mathematical law(?) that you distribute always after parenthesis 48÷2(9+3) is essentially 48 / (18 + 6), but it is far more simple to do 48÷2(12) first THEN distribute to 48÷24 The other way people have been getting 288 is just mathematically incorrect, regardless of interpretation, from what I learned.... Am I wrong or does everywhere else teach math wrong? o_0 You're distributing wrong. Because it's multiplication or division, you distribute both the 48 and the 2. It would go to (48÷2)*9+(48÷2)*3. If it were 48+2(9+3) then it would go to 48+(18+6) | ||
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