Solve this equation > 48÷2(9+3) = ?

15657596162108

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  • gomezzgomezz Posts: 44,622
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    lemonbun wrote: »
    Y(b + c) = (Yb + Yc)
    Y times (b + c) = Y * (b +c) = Y x (b +c)
    And Y * (b + c) = (Y * b + Y * c)

    What is the difference between the implied and explicit multiplier operand again?
  • lemonbunlemonbun Posts: 5,371
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    gomezz wrote: »
    And Y * (b + c) = (Y * b + Y * c)

    No
    Y * (b + c) = Y * b + Y * c - no brackets.
  • GneissGneiss Posts: 14,555
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    lemonbun wrote: »
    How many times - stop putting * or x signs where they are not stated.
    Y(b + c) = (Yb + Yc)
    Y times (b + c) = Y * (b +c) = Y x (b +c)
    The * or times sign means that the Y never goes inside the bracket, Y next to a bracket without an other operator means that the Y is part of the bracket (e.g. it is a factorial, etc.)
    Completely wrong...

    Y * (b +c) = Y x (b +c) = (Yb + Yc)

    Looks like the Y just ended up in those brackets.

    Feel free of course to provide links to any authoritative works backing up your claims though...
  • misha06misha06 Posts: 3,378
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    In my opinion the question is too ambiguous to be answered.

    I did an Engineering degree, which is very maths intensive and have faced much tougher questions than that.

    But I couldn't give you an answer that I could 100% believe was correct without clarification.

    Depending on your interpretation of mathematical rules, both answers could be deemed right.
  • lemonbunlemonbun Posts: 5,371
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    Gneiss wrote: »
    Completely wrong...

    Y * (b +c) = Y x (b +c) = (Yb + Yc)

    Looks like the Y just ended up in those brackets...

    It doesn't - it is Yb + Yc without the brackets. If it is (Yb +Yc), how come your answer to the original question was 288 ?
  • Mark.Mark. Posts: 84,922
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    lemonbun wrote: »
    It doesn't - it is Yb + Yc without the brackets. If it is (Yb +Yc), how come you get an answer of 288 to the original question?
    Because the 2 in the original question is "lost" in the division before it has a chance to multiply (9+3).
  • gomezzgomezz Posts: 44,622
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    lemonbun wrote: »
    No
    Y * (b + c) = Y * b + Y * c - no brackets.
    You honestly think the presence or absence of those parentheses (they are not brackets) in the expanded expression is significant? Please do not grow up to become a bridge builder. :eek:
  • GneissGneiss Posts: 14,555
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    lemonbun wrote: »
    It doesn't - it is Yb + Yc without the brackets.
    (Yb + Yc) = Yb + Yc

    There is NO difference here. You are looking at an isolated expression in which that brackets now have no meaning. You can put them back or remove them at will.
    lemonbun wrote: »
    If it is (Yb +Yc), how come you get an answer of 288 to the original question?

    Because in the original question Y = 48/2 Not 2

    And I did not come to an answer of 288 Google and several other programming languages did. I'm arguing that they applied to only rules applicable to arrive at their answer...
  • James TJames T Posts: 673
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    Just so I'm clear, have we got as far as a broad concensus that the debate hinges on whether 48/2(12) = 48/2*12 ? Are most people happy that the thing on the right =288 ? :confused:
  • Doctor_WibbleDoctor_Wibble Posts: 26,580
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    misha06 wrote: »
    Depending on your interpretation of mathematical rules, both answers could be deemed right.
    Well now that's just crazy talk!


    So, anyway - where do we all stand on 100/2π ?
    Do we have a circle or a TARDIS?
  • muntamunta Posts: 18,285
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    Well now that's just crazy talk!


    So, anyway - where do we all stand on 100/2π ?
    Do we have a circle or a TARDIS?

    You know, I don't think I have ever seen 2*π or 3*π. Its always 2π or 3π. Neither have I seen (2π) or (3π).

    I call circle :)

    disclaimer - just because I havn't seen it doesn't mean it doesn't exist. I'm using the Black Swan defense ;)
  • Season 74Season 74 Posts: 7,032
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    Congratulations everyone who has contributed to this meme. You have found a fundamental flaw in the use of BODMAS, BIDMAS, PEDMAS, etc. Can we now move on with our lives?

    48 / 2(9+3) = 288

    48 / x(9+3) = 2 when x = 2

    Please bare in mind that these two solutions are man made. There is no mathematical law written into our physical universe that says we have to do notation this way. It is just how we do it.
  • Season 74Season 74 Posts: 7,032
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    Just to add to that, because notation in maths is man made, if more than 50% of people get the wrong answer, does that make it the right answer?
  • John259John259 Posts: 28,466
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    Has anyone ever seen ab written as axb in a maths book, except perhaps when first explaining that ab means a times b?

    Has anyone ever seen a(b+c) written as ax(b+c) in a maths book?

    Has anyone ever seen two numbers multiplied together without a multiplication sign, perhaps written as (2)(3)?

    I think not.

    There are no such things as explicit and implicit multiplication. There is just multiplication, and according to the convention when it comes to the right of division in the same term it is done after the division.
  • njpnjp Posts: 27,583
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    What is your answer to the following expression?:

    6 x 10^5 / 3 x 10^5
  • John259John259 Posts: 28,466
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    njp wrote: »
    What is your answer to the following expression?:

    6 x 10^5 / 3 x 10^5

    Start with the powers:
    =6 x 100,000 / 3 x 100,000

    Then left to right:
    =600,000 / 3 x 100,000
    =200,000 x 100,000
    =20,000,000,000
    (=2^10 if you prefer that way of expressing it)

    EDIT: The final line above is incorrect and should read 2 x 10^10)
  • njpnjp Posts: 27,583
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    I guess that just about knocks it on the head for scientific notation then. Bummer.
  • tellytart1tellytart1 Posts: 3,684
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    njp wrote: »
    What is your answer to the following expression?:

    6 x 10^5 / 3 x 10^5

    From a scientific engineering background I'd state the answer is 2

    6 x 10^5 is actually meaning 6 followed by 5 zeroes, or 600000 (It's scientific notation for extremely large numbers, for instance the speed of light is approximately 300000000 m/s, or 3 x 10^8 m/s - self-evident here that you can't split the 3 and the 10^8 as separate numbers, it's one entity)

    Therefore it is 600000/300000 which is 2.

    However, because the original question is ambiguous, it could also mean 6 x (10^5/3) x 10^5, to be unambiguous it would need to be written as
    6 * 10^5
    3 * 10^5
  • ianxianx Posts: 9,190
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    John259 wrote: »
    =20,000,000,000
    (=2^10 if you prefer that way of expressing it)

    2^10 is 1024.

    20,000,000,000 would be 2 x 10 ^ 10.

    Tricky stuff this mathematical notation...
  • John259John259 Posts: 28,466
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    ianx wrote: »
    2^10 is 1024.

    20,000,000,000 would be 2 x 10 ^ 10.

    Tricky stuff this mathematical notation...
    Yes you are correct. My apologies.
  • gomezzgomezz Posts: 44,622
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    tellytart1 wrote: »
    Therefore it is 600000/300000 which is 2.
    Wrong. The normal rules of expression evaluation still apply. Now if you had used the alternative scientific notation as commonly adopted on calculators and computers of 6E5 / 3E5 then the answer would indeed be 2.
  • PamelaLPamelaL Posts: 67,688
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    Season 74 wrote: »
    Congratulations everyone who has contributed to this meme. You have found a fundamental flaw in the use of BODMAS, BIDMAS, PEDMAS, etc. Can we now move on with our lives?

    48 / 2(9+3) = 288

    48 / x(9+3) = 2 when x = 2

    Please bare in mind that these two solutions are man made. There is no mathematical law written into our physical universe that says we have to do notation this way. It is just how we do it.

    It's 'bear in mind'. :p
  • John259John259 Posts: 28,466
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    tellytart1 wrote: »
    self-evident here that you can't split the 3 and the 10^8 as separate numbers, it's one entity
    You shouldn't split them, but writing it the way it was has had the effect of doing so.

    3 x 10 ^ 8 isn't one entity, it's three separate numbers and two separate operations.
  • njpnjp Posts: 27,583
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    gomezz wrote: »
    Wrong. The normal rules of expression evaluation still apply. Now if you had used the alternative scientific notation as commonly adopted on calculators and computers of 6E6 / 3E6 then the answer would indeed be 2.
    Ah, but En or EXPn is simply shorthand for "x 10^n". Where did you get your new rule that applies only to calculators?

    [And why have you multiplied my original exponents by 10?!]
  • gomezzgomezz Posts: 44,622
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    njp wrote: »
    Where did you get your new rule that applies only to calculators?
    It is not a new rule. It is an update of the old rule placing the E operand in its appropriate place in the order of evaluation. Blame Texas.

    (I miscounted the zeroes earlier but it makes no difference to the argument)
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