48÷2(9+3) = ???

Discussion in 'Bad Dog Cafe' started by Agave_Blue, Apr 9, 2011.

48÷2(9+3) = ???

  1. 2

    190 vote(s)
    67.4%
  2. 288

    92 vote(s)
    32.6%
  1. Brian L

    Brian L Tele-Meister

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    Having talked it over with my 14 year old son, he screamed out "order of operations" the answer is "2".
     
  2. Northerntele

    Northerntele Tele-Holic

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    I read it as
    48
    2(9+3)

    Answer 2
    so I would say... Purple
     
  3. Buckocaster51

    Buckocaster51 Super Moderator Staff Member Ad Free Member

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    do it on an RPN calculator

    go ahead

    I dare you

    :)
     
  4. megafiddle

    megafiddle Former Member

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    This is getting more and more rediculouslessless.

    There is only one set of mathematical rules. They may have been different in the past,
    but there is only one currently accepted. The experession as written, and as commonly
    evaluated, equals 288.

    I have no doubt that many have been taught differently, but if you are going to speak
    in mathematical terms, you need to speak in a modern tongue.

    There was a time when pi was taught as being equal to 3. Things change.

    and I don't mean this offensivebly to anyone
     
  5. Mad Kiwi

    Mad Kiwi Friend of Leo's

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    Is this true or did you make this up to prove a point?

    How can the vaue of pi ever be less than to at least a couple of decimal places?

    Anyone who had a need to know pi in the past would have done so for practical reasons...that being said, wouldn't having rounded to the nearest whole number make it unuseable as a tool for calculation?
     
  6. bradymc92

    bradymc92 Tele-Meister

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    Now I remember why I failed math for 4 years it's all... er... not coming back to me at all! :oops::D
     
  7. getbent

    getbent Telefied Silver Supporter

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    This post rules in several unintentional ways.... ha ha! I love it!

    BrianL... is that the power of the Hollister School District I hear? ha ha!
     
  8. megafiddle

    megafiddle Former Member

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    It is true if you go back to biblical times, and it may even be true for modern
    times. There is some controversial evedence that some bible belt states were
    teaching this. I don't know for sure, but I did intend it as hyperbole

    I have heard people of my generation speak of learning pi as equal to 3,
    for whatever that's worth.

    And it is my point, though. There is a modern, universally accepted way to look at mathematical expressions.
     
  9. piece of ash

    piece of ash Friend of Leo's

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    Ya guys are all arguing over the correct way to pronounce "xrtck"...
     
  10. getbent

    getbent Telefied Silver Supporter

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    this was a half truth and was never actually passed nor enacted...

    an explanation of the incorrect value for pi in the bible

    your last point is reasonable... but, the problem exists because of the way the equation was written. People of reasonable measures of knowledge of algebra can be confused by the way the equation is stated... hence, the discussion....

    If it were truly simple, there would be no discussion.
     
  11. megafiddle

    megafiddle Former Member

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    Please elaborate.
    You may be using different rules of precedence.
    I see only one way to evaluate this.
     
  12. Phaze

    Phaze Tele-Holic

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    "Purple"
     
  13. Buckocaster51

    Buckocaster51 Super Moderator Staff Member Ad Free Member

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    Back in the "slide rule" days...

    ∏=3 was common

    ∏^2 = 10 was just as common.

    g/∏^2 = 1 worked

    Once again, I challenge you to evaluate this furshlugginer equation on an RPN calculator.

    If any of you are man enough! ;)
     
  14. kelnet

    kelnet Telefied Ad Free Member

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    As many in this Physics Forum point out, this so-called problem is an example of bad notation, and thus confusing. The Order of Operations does apply, but only once the notation has been corrected.
    http://www.physicsforums.com/showthread.php?t=488334

    Agave, you didn't create this equation. You found it, so don't get so defensive about it. It's a trick question designed to get people to argue. There is no correct answer. It just depends on how the notation is corrected.
     
  15. getbent

    getbent Telefied Silver Supporter

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    There is freedom in that. But, if you were to just read this thread, you'll find that there are reasonable, educated people who question the result.

    I have a number in my head that I would consider 'my answer'...

    but, the person who see absolutes in mathematics doesn't understand mathematics as well as he thinks.
     
  16. kelnet

    kelnet Telefied Ad Free Member

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    If there are 6 apples and you take away 4, how many do you have?
     
    Last edited: Apr 10, 2011
  17. getbent

    getbent Telefied Silver Supporter

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    my wife has 4.

    no, 6...

    no wait, she overheard this and tells me there is an entire bag in the pantry.
     
  18. J-man

    J-man Doctor of Teleocity Ad Free Member

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    The way I was taught leads me to 2.
     
  19. boilerup2004

    boilerup2004 TDPRI Member

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    A few words...

    I have two degrees in mathematics, and make a living "professing" about the subject (whatever that means). I came home from my first gig in a long time, and found work waiting for me here instead of leisure...

    -The order of operations hasn't changed in at least several decades. It's been that long since I first encountered it, and I'm pretty sure that I would have noticed if it had changed in the last 25 years or so.

    -The confusion is actually rooted in, of all things, fractions. Most people take for granted that an expression like "2/3" actually can represent two things--a number (you know, 2/3 of the way from 0 to 1 on a number line), or a process--2 divided by 3. In the latter case, many people forget that "grouping symbols" aren't restricted to just parentheses and brackets, but could include (among other things) absolute value bars, radicals, and (most importantly), the "fraction bar". Yes, it acts in the same manner as parentheses.

    As a result, modern scientific calculators generally have two buttons for division, one which reports the result in decimal form, and one which reports the result in fraction form. In the above example, a TI-30Xa (probably the most common scientific calculator ever produced), would report answers of 0.666.....67 and 2/3, respectively. The result is that depending on which type of division you use, you will get different answers for the same calculations, as decimal division usually doesn't treat the expression following the division symbol as being subject to priority grouping by default, where fraction division does. Also noteworthy is that most scientific calculators have separate buttons for subtraction and "negative", and confusing the two in a similar manner to what we've already discussed causes problems as well. For example, try computing -1^2 and (-1)^2 on several different calculators--you'll find that the same keystrokes produce different results. Better yet, try it on the SAME calculator using the negative and subtraction keys--you might find that you get a different result depending on which key you use!

    -The correct answer to the problem is 288. I go out of my way in remedial courses to nip the problem in the backside as soon as possible, as I've found it to be widespread among a group that is almost fanatical in their belief that they are working the problems correctly.

    -Also, as an Indiana resident, I am aware that there was once legislation proposed here suggesting that pi should be exactly 3. From wikipedia ("Indiana Pi Bill") I present some nonsense...

    ... his solutions of the trisection of the angle, doubling the cube and quadrature of the circle having been already accepted as contributions to science by the American Mathematical Monthly ...

    ...um, well, ahh, these have all been proven as impossible to do. Oh, by the ancient Greeks, at that. But anyhow, *if* you declare pi to be a certain value, then this guy can defy the laws of mathematics, and can probably make flying carpets and guitars that tune themselves.

    Nevermind, I guess Gibson did that.

    -One last tidbit. A friend of mine in graduate school found a way to use transcendental numbers to approximate integers. In particular, note that e^pi-pi is approximately equal to 20. Wierd, huh?
     
  20. J-man

    J-man Doctor of Teleocity Ad Free Member

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    8. I already had some apples.
     
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