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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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    288, no question.

    You can not assume another bracket enveloping also the 2.

    2(12) = 2 x 12.

    Once we've done the bracket we go back to normal convention, only another bracket would stop this, normal convention states that divide and multiply have the same weight, and you go from left to right.
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    (Original post by Jonty99)
    But you can't be sure if it should be read like that. You've assumed that.

    The way you've written it is probably how it was intended, but I don't think you can assume that. It's written ambiguously, so you just have to use BIDMAS from left to right.

    48/2(18)

    (24)(18)

    288

    It's just a badly written equation.
    To me it's either. 48/2(9+3) or 48/2 * (9+3)

    48/2(9+3) = \frac{48}{2(12)}
    48/2 * (9+3) = \frac{48}{2} * (12)
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    5,490 views in under 14 hours.
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    (Original post by Jonty99)
    It's written ambiguously, so you just have to use BIDMAS from left to right.
    On a point of logic: if you think there's a clear answer (that everyone should agree with), then surely it isn't written ambiguously.

    Although I think we can unambiguously agree that it's a badly written equation!
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    All this thread has done is prove relativity.
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    It's 2, q.e.d.
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    Not that this is going to help, but PLEASE STOP! The question is unclear! As written, there are two conflicting mathematical conventions:
    1) that calculations go left to right and
    2) that a(b+c) usually means (a(b+c))

    As a result, the answer cannot be definitive unless we have more brackets or we write in LaTEX and so get decent fractions!
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    (Original post by Haddock3)
    You're assuming there are brackets around the 2(9+3); technically the (9+3) goes atop the fraction by default. Equally, though, something written as the 2(9+3) is here is often assumed to go altogether as the denominator. Basically, the question is written badly, and the answer is thus unclear.
    This.
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    (Original post by DFranklin)
    On a point of logic: if you think there's a clear answer (that everyone should agree with), then surely it isn't written ambiguously.

    Although I think we can unambiguously agree that it's a badly written equation!
    I think there is a clear answer, because in a situation of ambiguity as to how the equation was intended to be written, we just have to calculate it as it actually is written. I think calculating it as it actually is written gives 288.
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    (Original post by jit987)
    5,490 views in under 14 hours.
    This is the Rebecca Black of the TSR Maths forum :p: And what an appropriate day of the week to be having this discussion!
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    BIDMAS

    Brackets Indices Division Multiplication Addition Subtraction

    Easy
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    (Original post by nuodai)
    This is the Rebecca Black of the TSR Maths forum :p: And what an appropriate day of the week to be having this discussion!
    "You have already rated a post by this user recently!"
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    (Original post by Jonty99)
    I think there is a clear answer, because in a situation of ambiguity as to how the equation was intended to be written, we just have to calculate it as it actually is written. I think calculating it as it actually is written gives 288.
    So in other words, you don't think it's written ambiguously - the question is whether the person who wrote it meant what they wrote.

    Not a bad way of looking at it actually.

    (I would interpret 1 + x / x - 1 to be (1+x)/(x-1), but at the same time the "correct" value is clearly 1 {edit}).
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    (Original post by DFranklin)
    (I would interpret 1 + x / x - 1 to be (1+x)/(x-1), but at the same time the "correct" value is clearly 0).
    Or, indeed, 1 :p: [Unless 1+1-1=0 and I'm mistaken.] Although that begs the question of how you'd write 1+\frac{x}{x-1}. Thank god for LaTeX.
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    (Original post by jit987)
    "You have already rated a post by this user recently!"
    "You have reached the limit of how many posts you can rate today!"

    Sigh.
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    (Original post by DFranklin)
    So in other words, you don't think it's written ambiguously - the question is whether the person who wrote it meant what they wrote.
    Yes, exactly.
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    (Original post by nuodai)
    Or, indeed, 1 :p:
    Indeed. {swears}

    Although that begs the question of how you'd write 1+\frac{x}{x-1}. Thank god for LaTeX.
    1 + (x / x-1) would work for me. (Or 2x-1 / x-1. We are mathmos, after all).
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    (Original post by py0alb)
    lol. Of course it is. It means exactly the same thing. and

      2^{-1}

    is also exactly the same thing. (you might not have come across that one yet)

    Most undergraduates and above simply make the difference clear by spacing their formulas appropriately. Its perfectly fine to write:

    x = 48/2 __ . __ (9+3)

    I wouldn't mark down an undergrad who gave that as an answer.
    Thanks for the patronising reply, I'm 25 years old with a F. Maths A at A-level and a highly numerate job.

    Maths notation is really clear on this point. The answer is 288.

    You are still wrong. As I've said, when using vertical fractional notation, the vertical positioning of elements of the equation effectively functions as parentheses.
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    Cant believe this is still going on. Need to make it mandatory from now on that any questions in the Maths forum be posted in LaTex form.
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    (Original post by nuodai)
    (Original post by jit987)
    "You have already rated a post by this user recently!"
    "You have reached the limit of how many posts you can rate today!"

    Sigh.
    Talk about love!
 
 
 
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