EPTuse pemdas, the order of operations
Parentheses 9+3 is 12 so 48÷2(12)=?
Exponents is none
Multiply 2(12) is 2 * 12 = 24 so 48÷24 =?
Divide 48 ÷ 24 is 2 so 2 =?
Addition none
Subtraction none
2 is left so 2 is the answer
A Simple Math Problem? - Page 80
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astb
United States10 Posts
use pemdas, the order of operations Parentheses 9+3 is 12 so 48÷2(12)=? Exponents is none Multiply 2(12) is 2 * 12 = 24 so 48÷24 =? Divide 48 ÷ 24 is 2 so 2 =? Addition none Subtraction none 2 is left so 2 is the answer | ||
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Crushgroove
United States793 Posts
On April 09 2011 03:00 andrewwiggin wrote: http://forum.bodybuilding.com/showthread.php?t=133417023 Read the first post. It explains WHY 288 is right much better than I can be bothered to right now.... People should really really REALLY go read that post. I was trying to come up with all the incidental and incorrect arguments and write out why they are wrong... but this guy did it for me. Read it. | ||
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yrag89
Malaysia315 Posts
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Crushgroove
United States793 Posts
On April 09 2011 03:21 astb wrote: 48÷2(9+3)=? use pemdas, the order of operations Parentheses 9+3 is 12 so 48÷2(12)=? Exponents is none Multiply 2(12) is 2 * 12 = 24 so 48÷24 =? Divide 48 ÷ 24 is 2 so 2 =? Addition none Subtraction none 2 is left so 2 is the answer This is incorrect because "PEMDAS" places multiplication and division as the same priority, done in order left to right. Therefore, your multiply step is done in the wrong order. The division would come first. "P" comes first, then "E", then "MD" then finally "AS" all in order left to right. Check that text book again. EDIT: 9 post troll? Sorry I got reeled in.  | ||
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Severedevil
United States4839 Posts
On April 09 2011 00:30 TestSubject893 wrote: You aren't using implied multiplication. I think the discussion would be much different if the original post contained the expression as you wrote it. Lol. The entire discussion would be, "I got 2 because PEMDAS says Multiplication before Division" "Actually, PEMDAS puts Multiplication and Division on the same tier of precedence, it's a slightly misleading acronym" "Oh, thanks!" Instead, it's a clash between people who're aware of differing conventions for implicit multiplication versus explicit multiplication, and people who aren't + refuse to learn. | ||
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bonifaceviii
Canada2890 Posts
For those confused about the apparent disconnect between the final poll and the first one, this math trick pits your grade school brain against your high school brain. Seriously, when's the last time you saw the ÷ notation in a math problem? | ||
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Ceril
Sweden1343 Posts
On April 09 2011 03:21 astb wrote: 48÷2(9+3)=? use pemdas, the order of operations Parentheses 9+3 is 12 so 48÷2(12)=? Exponents is none Multiply 2(12) is 2 * 12 = 24 so 48÷24 =? Divide 48 ÷ 24 is 2 so 2 =? Addition none Subtraction none 2 is left so 2 is the answer You forget M&D are ranked the same and should be done left to right. When you multiply 2(12) you have 48/2 to the left still to evaluate and left should be evaluated first. edit:Damn, how many people are hawking this thread and posting. On the bright side: I've just gotten interested in math and will be stroking myself against my black edition Calculus for an hour and then be back and read additional ~15 pages =) | ||
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Yurie
12175 Posts
On April 09 2011 03:21 Crushgroove wrote: People should really really REALLY go read that post. I was trying to come up with all the incidental and incorrect arguments and write out why they are wrong... but this guy did it for me. Read it. We all know 288 is correct. What we are talking about is the fact that it isn't the first answer everybody comes to due to how parentheses are written in lazy mathematics. Basically it is an argument about what the 2 prior to a parentheses means. Do you add a * prior to the parentheses or not in a normal situation? | ||
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SharkSpider
Canada606 Posts
Some people are taught to approach these problems in a way that results in 2, others in the way that results in 288. I believe any official text on the use of division or / would give the 288, but anyong coming at math from a higher level, or from a country that teaches math properly (see: not North America) would probably be fairly clueless. | ||
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Danjoh
Sweden405 Posts
On April 09 2011 03:17 rackdude wrote: Why do people always think there is one correct answer when it comes to math... the moment you start doing math you realize how wrong that is... + Show Spoiler + There is no correct answer here. There is a correct answer for each interpretation of the input, but since the input is ambiguous in the most proper sense (it would require one more set of brackets), then depending on how you put the missing set of brackets there is a correct answer. A lot of people have an interpretation of the input that reads from left to right and applies the order of operations and thus brackets like (48÷2)(9+3), others (including a lot of calculators) interpret the input when involving division signs as top divided by bottom until there's a space (like in mathematica), and thus they would bracket it as (48)/(2(9+3)). For either of those you will get a correct answer, but for the original question the correct answer is that you have a syntax error and thus are just using shorthand and if people misinterpret what you meant by your shorthand then you should probably change the way you wrote the problem. Soo.... anyone dare to use that argument to get their scores up on a math test? The different methods I've tried all resulted in 288, if you for some reason got a syntax error, you probably just need to add the * between the 2 and the (. And I see some arguments that ÷ is different from /. There isn't. My keyboard has the symbolr ÷, but types out /, my calculator has the symbol ÷, but types out /, my friends calculator has the symbol ÷ and also types out ÷. And his calculator also calculated 48÷2(9+3) as 288. Would you also argue that 2*2 is different from 2x2? (assuming that in this case x is the operator and not the variable) | ||
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Crushgroove
United States793 Posts
On April 09 2011 03:25 Yurie wrote: We all know 288 is correct. What we are talking about is the fact that it isn't the first answer everybody comes to due to how parentheses are written in lazy mathematics. Basically it is an argument about what the 2 prior to a parentheses means. Do you add a * prior to the parentheses or not in a normal situation? I wish it were that simple Yurie.... but I doubt that people actually know that its correct. My impression after reading this whole thread is that there are people who actually think the answer is 2. For one reason or another... and I was talking to that percentage of the population. | ||
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chonkyfire
United States451 Posts
jeans cost 9 dollars each, shirts cost 3 dollars each 48 / (9*2+3*2) = 48/2(9+3) ?? Or are they different? | ||
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floor exercise
Canada5847 Posts
Brackets, then exponents, then division/multiplication left to right and finally addition/subtraction left to right | ||
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astb
United States10 Posts
the 48÷2*12 then multiply or divide in order of left to right 48÷2 = 12 12*12 = 144 is the answer | ||
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rackdude
United States882 Posts
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Crushgroove
United States793 Posts
On April 09 2011 03:04 Jyxz wrote: To all the elitists who think its 288.... 48/2x x= (9+3) solve please. uh oh.....? You are also incorrect. If x actually = (9+3) then the value of 'x' would include the parentheses, and therefore yield a solution of 288. If you wrote instead: x = 9+3, then you are writing a different problem all together. | ||
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Bellygareth
France512 Posts
On April 09 2011 03:29 astb wrote: parentheses is first to 9+3 is 12 the 48÷2*12 then multiply or divide in order of left to right 48÷2 = 12 12*12 = 144 is the answer AHaha what? 48/2 =12? Mathematics is hard xD | ||
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SharkSpider
Canada606 Posts
On April 09 2011 03:29 astb wrote: 48÷2 = 12 What is this I dont even Seriously, though. I doubt many of the people making the huge "You're all dumb THIS is the answer" posts can actually define 288 or 2. Or, for that matter, addition, subtraction, multiplication or division. | ||
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Pufftrees
2449 Posts
On April 09 2011 03:27 SharkSpider wrote: Some people are taught to approach these problems in a way that results in 2 Where do they teach Math incorrectly? I would like to know, seriously. | ||
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chonkyfire
United States451 Posts
On April 09 2011 03:33 SharkSpider wrote: What is this I dont even Seriously, though. I doubt many of the people making the huge "You're all dumb THIS is the answer" posts can actually define 288 or 2. Or, for that matter, addition, subtraction, multiplication or division. well if 2(9+3) is the same as (9*2+3*2) then it's 2 is it at all justifiable at any point to write it 48/2(9+3) as compared to 48/24? | ||
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