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Math Quiz

Discussion in 'General Motorcycling Discussion' started by shabby, Mar 11, 2005.

  1. now this was a simple question asked by someone on another chat site, since then it seems to have escalated into full out warfare and the professors are not doing so well.

    ok, so this is the question (easy as)
    5-2 + 4x2 =

    what does it equal??
  2. Shouldn't it be maths , math is american . Thought i would point this out as there seems to be a couple of people who dont like americanism . And no im not going to answer the question , as im quite certain my total will be wrong .
  3. Ok I'll bite. eleven
  4. When I went to school... some 29 years ago, this was the rule...
    + and - have equal precedence, and so are evaluated ``left to right''; but are only considered after *, / and %

    so, that'll be 4*2 = 8 plus the 5 (making 13) minus the 2 which will give 11

    But heh, I was a front row forward..... "Errr, I'm not very smart... but I can lift 'evy weights....." :LOL:
  5. Tassie boy like you could ad that up on your hands :p
  6. nope, too heavy to lift me knuckles off the ground :shock:
  7. The correct answer is.......................................................


    BIMDAS is the term standing for:

    An incorrect comment earlier about mulitplication and division having equal priority, and addition and subtraction, is only correct under certain circumstances. You also cannot swap equations around as per an earlier example without making an equal and opposite change on the other side of an equation. In this example there is no other side!!

    Therefore the equation should proceed as thus:

    = 5-2+8 (having done the multiplication first)
    =5-10 (next having done the additon)
    = - 5

    Just my humble opinion
  8. WTF shabby
    cant u count

    =5-2+8 does not equal 5-10. -2+8 is 6 therfore 5 + 6 is 11
    or u can do it 3 + 8 equals 11
  9. It would equal -5 if the equation was


    Wouldn't it? :? Actually, I'm quite sure :p

    I worked it out to be 11 as well....

    :D :D :D
  10. and the answer is ... the question is wrong.

    if you set out to be ambiguous,
    then you are responsible for what ever answer you get.

    the person asking the question should attempt to communicate explicitly and effectively,

    (5-2) + (4x2) = 11
    5 - (2 + (4x2)) = -5

    ... or what ever variation you want.
  12. rofl shabby, owned.
  13. I would have said 11, because from my schooling, it was brackets, multiplication/division (equal priority), addition/subtraction (again, equal priority).

    Read this way, 11 is the answer.

    Read your way, with priorities on the addition/subtraction, then -5 is correct.
  14. As a teacher, my humble opinion could have us in trouble, BUT

    The circumstances in which + & - are not equal occurs when brackets are involved.

    There are no brackets in this equation, therefore it should be completed in order.
    5-2+ 4x2=

    Of course it could also work like this:
    5-2 + 4x2=
    5-2 +8=
    Now, if you do the addition first, it would have to be multiplied by 5 as when there is no symbol, it defaults to multiplication. As in:
    5X=30 when X=-2+8 or 6.

    The point to be made is that unless there are brackets or x & / verses + & - then the correct procedure is to work from left to right. I would put a big red cross next to anything except 11.
  15. 11.

    Unless the 'professors' are imagining brackets... or you neglected to put them in.

    Regardless, I can't see a practical situation where that equation would arise in that form, without the answer being clear. Pointless.
  16. Yea Carver.

    We should make shabby use a HP or write a program in Forth to prove his point.

    Shabby, thou shalt bracket if thy wishes thy answers to be consistent.

    Answer is 11. A pox of flatulence for a thousand years on anyone who says differently :p
  17. Is that when the + and - have different influence on the inside of a bracket?

    ie. -x(-y+z) :?:

    :D :D :D
  18. What professors are you talking about? Art's professors? bahahahahah :LOL:

    Asking any maths professor, or a good year 12 student, they'd say that the above question is the same as:

    = 5 + (-2) + 4x2

    As such, performing the calculation, multiplication and division takes precedence over addition and subtraction.

    = 5 - 2 + 8
    = 3 + 8
    = 11.

    Funny enough, I'm actually tutoring a y11 right now in Mathematical Methods ;p.
  19. hey shabby its paulas son JACK what does this equal??