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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 Tizmo)
    THIS.

    Just put the equation into my Casio FX85GT plus and I got 2.
    Im in bed and tying this on my phone so i have no calculator to hand, though my take on the issue is:

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

    48{division sign here}2(9+3) = 2


    Any1 in agreement with me?
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    (Original post by Simplicity)
    PEDMAS.

    Why you guys getting 288. You must be doing something wrong?

    Do you guys even do Maths?


    I'd have thought brackets, then division, then multiplication.

    So (9+3)=12

    48÷2(12)

    Then division.

    (24)(12)
    =288

    And anyway, if you're so certain that it's 2, why did you start the thread?
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    No no no
    Check your working out

    maybe error working out
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    Follow BIDMAS and you'll get 288.

    Brackets
    Indices
    Division
    Multiplication
    Addition
    Subtraction
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    The way I see it and have learned it, when simplifying the brackets, it still stays as 2(12).

    so 48÷2(12), so the multiplication is done first, so 48÷24, which is 2.
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    (Original post by bloomblaze)
    I thought it would be 288 if the expression read (48/2)(9+3) ie brackets, but without brackets around the first bit it would be 2.

    Anyone with me?? Or am i talking nonsense?
    Yes but 48÷2(9+3) and 48/2 x (9+3) are the same thing. BIDMAS clearly explains that division is before multiplication. Hence 288.

    I'm quite worried about the number of people who thought this was 2...
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    (Original post by Simplicity)
    PEDMAS.

    Why you guys getting 288. You must be doing something wrong?

    Do you guys even do Maths?
    The 'DM' part. See my working.
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    http://www.wolframalpha.com/
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    (Original post by Tizmo)
    The way I see it and have learned it, when simplifying the brackets, it still stays as 2(12).

    so 48÷2(12), so the multiplication is done first, so 48÷24, which is 2.
    Multiplication and division are equally-weighted so you work from left to right (after the brackets and indices have been dealt with) - one has no precedence over the other.
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    N(Y) = N x Y right? Unless there is a symbol, assume its x.

    (I haven't done maths in 3 years, so don't take my word for it...)
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    na na na

    you have to add then add and then multiply out the things
    then add the things then subtract the thing from the thing

    and then AL a BOOM you have ur trupid answer
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    (Original post by bloomblaze)
    Im in bed and tying this on my phone so i have no calculator to hand, though my take on the issue is:

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

    48{division sign here}2(9+3) = 2


    Any1 in agreement with me?
    (Original post by Tizmo)
    The way I see it and have learned it, when simplifying the brackets, it still stays as 2(12).

    so 48÷2(12), so the multiplication is done first, so 48÷24, which is 2.
    As I said earlier, you have 48 ÷ 2(9+3). 9+3 = 12, so you have 48÷2(12). If you then replace (12) with y, and 2 with x, you have 48÷x(y) or 48/x(y). x(y) = xy = x * y . So you have 48/x * y. x is 2, so you have 24 * y, y is 12 so you have 288.
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    Wait, of course! It is 288 because of the Order of Mathematical Equations, aka BEDMAS/BIDMAS, like others have mentioned.

    http://math.about.com/library/weekly/aa040502a.htm

    So, basically:
    48÷2(12)

    can be rewritten as

    (48÷2)(12)

    Division comes first

    (24)(12) =

    288

    Serves me right for trying to calculate at this hour!

    Just looking at my notes from college, this is what I have written down when we went over the mathematical rules:

    1) Brackets
    2) Exponents/Logarithms
    3) Division
    4) Multiplication
    5) Addition/Subtraction
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    i'm gonna plop for 288
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    288

    48÷2(9+3)= 48÷2x12=24x12=288
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    (Original post by andrewmc96)
    Multiplication and division are equally-weighted so you work from left to right (after the brackets and indices have been dealt with) - one has no precedence over the other.
    Division has precedence normally, I was taught so in Maths, and usually you expect division to have precedence in the 3rd gen languages I have come across (C, C++, Java, etc).
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    http://www.wolframalpha.com/input/?i=48%2F2x+at+x%3D12

    It's 2.
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    (Original post by rmhumphries)
    Division has precedence normally, I was taught so in Maths, and usually you expect division to have precedence in the 3rd gen languages I have come across (C, C++, Java, etc).
    My maths teacher taught us that neither had precedence over the other. Oh well, guess he was kinda wrong.
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    (Original post by rmhumphries)
    Division has precedence normally, I was taught so in Maths, and usually you expect division to have precedence in the 3rd gen languages I have come across (C, C++, Java, etc).
    I was always taught that division and multiplication (as they are effectively the same thing - 2x0.5=2/2) and addition and subtraction (again, 2-2 = 2+(-2)) are treated equally, so it now goes left to right. Therefore, strictly speaking, I suppose it is 288, but really it's just a poorly written equation.
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    48 ÷ (2 x 12) is a totally different calculation to 48 ÷ 2 x 12.

    48 ÷ (2 x 12) = 2
    48 ÷ 2 x 12 = 288
 
 
 
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