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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 py0alb)
    It's worth noting that its largely irrelevant because no-one past GCSE level uses the divide sign. This is the reason we use either:

    48
    _______

    2(9+3)

    or

    48/2 . (9+3)

    depending on which we mean.
    There is no oerational difference between the two division signs, they are merely typographical variations.
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    (Original post by Get me off the £\?%!^@ computer)
    You're funny.

    I'm guessing you didn't read my post properly.

    I'm not arguing about rules of precedence. I hope we both understand them very well. I'm talking about conventions adopted by manufacturers of calculators.

    Am I allowed to do that?
    Sure, and I contributed 2 more examples to that, however that isnt what this thread is about and you clearly said that only you and that other numpty "understood".
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    (Original post by HistoryRepeating)
    You are right when you take 48÷2(9+3) to be 48/2(9+3)
    These are identical in meaning.

    You are wrong on the bold bit. You dont multiply out brackets before applying the left-to-right rule - why would you?

    Again you are just basing this on your gut instinct (which is sadly wrong) rather than the actual notation standards.

    By the way do you interpret 1/2x as half x or 1/(2x) ?
    1/2x=1/2x it'd only be 1/2 x if it were displayed like 1/2 (x)
    It's the way the question is presented. I keep emphasizing this.
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    (Original post by Get me off the £\?%!^@ computer)
    I'm talking about conventions adopted by manufacturers of calculators.

    Am I allowed to do that?
    Post 192 will demonstrate to you that the calculator manufacturers don't know what day of the week it is.
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    I'm disgusted at education today! The bit you are arguing about is not included in BODMAS or whatever you use. Coefficients (like 2x, 3y, 4(2)) do not have multiplication signs, and they are considered BEFORE division - do not treat coefficients as having a multiplication sign between them - they are 'coefficient'; they are as one.

    The answer isn't one though, it's two.
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    48/2(9+3)

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

    (48/2)(9+3)
    =(24)(12)
    =288
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    i would solve brackets first 9+2=12
    12x2=24

    then 48/24=2

    that is how i would have solved it don't know if it's right :dontknow:
    i'm curious what is the answer :curious:
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    (Original post by HistoryRepeating)
    That isn't true. Please cite any source.

    Multiplications using a heavy dot, or a dash, get done first. Multiplicands are dealt with normally.
    multiplication with a dash? the source is me, and i believe it to be true because that's what we were told in A level maths.
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    (Original post by smiffhead)
    I'm disgusted at education today! The bit you are arguing about is not included in BODMAS or whatever you use. Coefficients (like 2x, 3y, 4(2)) do not have multiplication signs, and they are considered BEFORE division - do not treat coefficients as having a multiplication sign between them - they are 'coefficient'; they are as one.

    The answer isn't one though, it's two.
    Please cite any source that states that coefficients should be considered BEFORE (division and multiplication).

    PS: I'm not using BODMAS or any other mnemonic, but the actual rules of mathematical notation which are used at a university level.
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    Its 288.

    Just use BODMAS. It doesn't matter how the question is presented.

    1) Brackets first - (9+3) = 12

    You now have 48÷2(12)

    2) Division before multiplication - 48÷2 = 24

    You now have 24(12)

    3) Multiplication - 24 x 12 = 288


    Final Answer = 288

    There is no debate. The people who are saying 2 think that brackets also means you have to multiply the brackets out before division. This is wrong as division is done before multiplication. Brackets in BODMAS means calculate whatever is inside the brackets first.

    Wolfram agrees with me: http://www.wolframalpha.com/input/?i...B72%289%2B3%29
    and Wolfram is never wrong!
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    (Original post by smiffhead)
    It is two...what you guys are missing out is the fact that multiplications without a multiplication sign (such as ab, or 3y, 2x) should be done first - this is not included in any variant of bodmas.
    Wrong.
    http://www.wolframalpha.com/input/?i=48%2F2%289%2B3%29
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    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
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    (Original post by F1Addict)
    This is wrong as division is done before multiplication.
    :no: No. No. No. Right answer, wrong reason.
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    (Original post by HistoryRepeating)
    Please cite any source that states that coefficients should be considered BEFORE (division and multiplication).

    PS: I'm not using BODMAS or any other mnemonic, but the actual rules of mathematical notation which are used at a university level.
    THISSSSSSS
    I can't believe the amount of people who are pretty much just making up facts in this thread. I'm with you HistoryRepeating.
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    http://www.thestudentroom.co.uk/show....php?t=1600083
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    I swear it is 288 because the 'B' in bodmas/bidmas/whatever refers to the terms inside the bracket, and it does then just become 48 / 2 x 12

    oh the confusion....!
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    That's a good way of approaching maths - democracy. Can we also vote on what 2+2 should equal for the next five years?
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    (Original post by Good bloke)
    :no: No. No. No. Right answer, wrong reason.
    Confused. :confused:
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    (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?
    This.

    Though I'm interested to see whether as large numbers are wrong as it seems.
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    I've gone with the basic rules of maths?

    Also my calculator
 
 
 
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