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48÷2(9+3) = ? watch

  • View Poll Results: 48/2(9+3)
    2
    117
    52.47%
    288
    106
    47.53%

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    (Original post by smiffhead)
    but you can't use that identity at the top to imply anything about precedence.
    Which is why there is an argument about this, and the answer is 2.
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    (Original post by Simplicity)
    Sorry, but some people at the Maths computer cluster was arguing about this.

    I say it's 2.
    It is 2 , 9+3=12 and 2 x 12 is 24 so its 48÷24=2
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    (Original post by Simplicity)
    Sorry, but some people at the Maths computer cluster was arguing about this.

    I say it's 2.
    LOL mate were those people at the computer cluster meat heads.

    This is currently a debate raging large in the intellectual arena that is bodybuilding.com's misc.
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    (Original post by Jallenbah)
    You realise splitting it up as a fraction onto multiple lines is identical to using brackets? There is no ambiguity here.
    There is because there are NO brackets used to split the fraction/division. For it to read the bottom fraction, the calculation should be written as 48÷(2(9+3)).
    Without those brackets, the rules of BIDMAS separate it as (48÷2)(9+3).
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    (Original post by Iqbal007)
    It is 2 , 9+3=12 and 2 x 12 is 24 so its 48÷24=2
    Why are you performing the multiplication before the division? The multiplication is outside the brackets.
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    (Original post by Planto)
    Why are you performing the multiplication before the division? The multiplication is outside the brackets.
    It doesn't make a difference, but i did it as it was multiplying the brackets first.
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    You are again missing the point...
    -nothing to do with how the numerator and denominator are grouped in a fraction,
    -the point is that ANY multiplication implied by juxtaposition is not just a multiplication, it involves a coefficient,
    -which by definition is joined to the bit after it (multplicand or variable or whatever), and must treated as together!

    answer's 2
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    quoted people

    (Original post by duck6)
    There is a lot of disagreement over the answer to this question so I though't I'd start a poll to see what everyone thinks

    (Original post by Good bloke)
    That's a good way of approaching maths - democracy. Can we also vote on what 2+2 should equal for the next five years?

    (Original post by Jallenbah)
    This.

    Though I'm interested to see whether as large numbers are wrong as it seems.

    (Original post by gummers)
    I've gone with the basic rules of maths?

    Also my calculator

    (Original post by Rancorous)
    Think this sums up how ridiculous this forum is with most of its threads. It's basic maths - you don't get an 'opinion'. And we all have to respect other people's opinions no matter how retarded they are, because God if someone who has acquired high rep comes up with something moronically stupid and you tell them so, you're in the red.

    (Original post by Aeschylus)
    I've gone with the option of having a girlfriend and a life

    (Original post by Good bloke)
    At the time of writing the score stands 9-5 in favour of the 288s. It shows how poor democracy can be as a decision-making system when over a third of the public doesn't even nderstand year 7 maths.

    (Original post by nuodai)
    Or rather that it's ambiguous notation and that settling it with a poll is a stupid idea.

    (Original post by Good bloke)
    Nobody could disagree with that, surely?

    (Original post by Jingers)
    Lies. You just wanted to create a thread to see how many replies you get.

    (Original post by nuodai)
    Indeed.

    Up next: a poll on whether 18÷6÷3 equal to 1 or 9.

    (Original post by Good bloke)
    I think, given the budget cuts and Portugal's problems, we should postpone that for a future programme.

    (Original post by tripleeagle)
    My calculations and my calculator (http://www.wolframalpha.com/input/?i...B72%289%2B3%29) agree that it's 288

    (Original post by Miss Anonymous)
    I think it's 2.
    And so does my calculator

    This 48/2(9+3) could be either

    1) (48)/(2(12)) = 48/24 = 2

    .

    2) (48/2)(9+3) = 24(12) = 288


    LATEX format

         \[\frac{48}{2(12)}= \frac{48}{24}= 2

    or

      (\frac{48}{2})(9+3) = 24(12) = 288\]
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    (Original post by smiffhead)
    but you can't use that identity at the top to imply anything about precedence.
    That's not the point of it, it's for people who (wrongly) believe that 2(9+3) is somehow different from 2 \times (9+3) .

    Multiplication and division take equal precedence because that is how they are defined. http://en.wikipedia.org/wiki/Order_of_operations

    (Original post by Sovietpride)
    Whilst true, and i would, as i always did in gcse and a level, blame the question.
    But, why have you have suddenly removed brackets?

    I.e, you put 48 ÷ 2 x 12

    When it still should have been

    48 ÷ 2(12)

    ?
    See above, there is no difference.
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    dont you do the brackets before anything else?
    been alooonnng time since i did maths...
    i got 2...
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    (Original post by Planto)
    Why are you performing the multiplication before the division? The multiplication is outside the brackets.
    because it's not a simple multiplication, they are coefficients - there is no multiplication sign - so they must be treated as together.
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    (Original post by surina_xxx)
    i asked my mum, shes an A level teacher, the answers 2
    Knowing the more complicated stuff in maths doesn't mean you know the easier stuff.

    One of my lecturers knows a hell of a lot about real variable theory but that doesn't mean he can answer any of my quantum questions.
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    (Original post by Limoncello)
    x
    But the first of your solutions requires you to process an equal precedence operator outside the parentheses (the multiplication) before one to its left, and therefore out of the correct order.
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    Regardless of whether you think the answer is 2 or 288, can people avoid responses like "can't you do 6th grade maths?". There are people with Maths degrees supporting both answers.
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    (Original post by IchiCC)
    That's not the point of it, it's for people who (wrongly) believe that 2(9+3) is somehow different from 2 \times (9+3) .

    Multiplication and division take equal precedence because that is how they are defined. http://en.wikipedia.org/wiki/Order_of_operations



    See above, there is no difference.
    whacking a multiplication sign in completely changes the situation.
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    (Original post by smiffhead)
    You are again missing the point...
    -nothing to do with how the numerator and denominator are grouped in a fraction,
    -the point is that ANY multiplication implied by juxtaposition is not just a multiplication, it involves a coefficient,
    -which by definition is joined to the bit after it (multplicand or variable or whatever), and must treated as together!

    answer's 2
    A coefficient isn't just sitting idly for viewing pleasure. The 2 in 2x isn't just sitting there waiting for you to plug in a value of x, it's already multiplying the x. Hence multiplication, hence 288.

    (Original post by smiffhead)
    whacking a multiplication sign in completely changes the situation.
    The multiplication sign is implied since the 2 is next to the bracket.

    5(x+1) = 5 \times (x+1) is a true statement.
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    I got 36.
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    2(9+3) is different from 2 x (9+3). the former implies that they are coefficients, and as such you can't split the apart.
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    (Original post by IchiCC)
    That's not the point of it, it's for people who (wrongly) believe that 2(9+3) is somehow different from 2 \times (9+3) .

    Multiplication and division take equal precedence because that is how they are defined. http://en.wikipedia.org/wiki/Order_of_operations



    See above, there is no difference.
    Nobody is arguing that division or multiplication take precedence. Unless they're silly anyway because they don't.

    What i'm arguing is why you've removed the brackets when they're simply not done with yet?

    Edit: Nvm.

    i'm used to crappy C1-4 questions and know what they're after -.-'

    *strictly* speaking,

    If it was 2 it would be

    = "48÷(2(9+3))" ?
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    i don't get what you are saying. it certainly doesn't seem to relate to what i said. it is, however, correct, but you still have the wrong answer.
 
 
 

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