218358 Bullies, 8005 online  
  • Register
Our Sponsors:

Results 201 to 210 of 267
Page 21 of 27 FirstFirst ... 111718192021 22232425 ... LastLast
Sponsored Links Spacer Image
  1. Rivington is offline
    Rivington's Avatar

    Senior Member

    Join Date
    Jun 2007
    Location
    East Bay, CA
    Posts
    4,733

    Posted On:
    11/08/2012 4:10pm

    supporting member
     Style: Taijiquan/Shuai-Chiao/BJJ

    2
    Hell yeah! Hell no!
    Quote Originally Posted by Mr. Machette View Post
    Can you give me a quick algebra tutorial on this? My brain is making the same mistake as that TI 82.

    6/2(2+1)

    6/2(3)
    3(3)

    3*3 = 9
    Wrong operation. Or rather, the Casio is answering:

    6/2(2+1)

    Which is

    6/2(3)

    Which is

    6/6

    Which is

    1.

    Basically it's answering
    Six divided by the result of 2 multiplied by the sum of 2 plus 1.

    You're answering six divided by two multiplied by the sum of 2 plus 1.

    It's a notation problem.
  2. Tranquil Suit is online now
    Tranquil Suit's Avatar

    On hiatus

    Join Date
    Jul 2009
    Posts
    3,442

    Posted On:
    11/08/2012 4:12pm

    supporting member
     Style: Getting fat.

    --
    Hell yeah! Hell no!
    I also think the answer is 9.

    6/2*3 == 6*2^-1*3 =/= 6*(2*3)^-1 == 6/(2*3)


    / and * have the same operation priority and we comptute from left to right, no?

    (tab) Forum > Forum Actions > General Settings > in Thread Display Options > Number of Posts to Show Per Page: 40
  3. goodlun is online now
    goodlun's Avatar

    Senior Member

    Join Date
    Jun 2008
    Location
    Ramona
    Posts
    4,616

    Posted On:
    11/08/2012 4:12pm

    Join us... or die
     Style: BJJ

    --
    Hell yeah! Hell no!
    Quote Originally Posted by Mr. Machette View Post
    Can you give me a quick algebra tutorial on this? My brain is making the same mistake as that TI 82.

    6/2(2+1)

    6/2(3)
    3(3)

    3*3 = 9

    What am I missing here? (It looks like you go from 3(3) to 3/3 which tells me there's some principal or basic rule that I've forgotten.)

    Sorry if I sound like a dumb ass. Just trying to avoid a slip into early senility and I haven't done any algebra in at least five years.
    No problem what you are missing is the order of operation
    PEMDAS
    6/2*(2+1) Parentheses
    Exponents would be next but we don't have any
    6/2*(3) Multiplication
    6/6 Division
    Addition (we have none)
    Subtraction (we have none)
    1
  4. Tranquil Suit is online now
    Tranquil Suit's Avatar

    On hiatus

    Join Date
    Jul 2009
    Posts
    3,442

    Posted On:
    11/08/2012 4:16pm

    supporting member
     Style: Getting fat.

    1
    Hell yeah! Hell no!
    http://en.wikipedia.org/wiki/Order_of_operations


    ...In the United States the acronym PEMDAS is common. It stands for Parentheses, Exponents, Multiplication, Division, Addition, Subtraction. Canada uses BEDMAS and the UK uses BIDMAS or BODMAS. In Canada and other English speaking countries, Parentheses may be called Brackets, or symbols of inclusion and Exponentiation may be called either Indices, Powers or Orders, which have the same precedence as Roots or Radicals. Since multiplication and division are of equal precedence, M and D are often interchanged, leading to such acronyms as BOMDAS.

    Similarly, there can be ambiguity in the use of the slash ('/') symbol in expressions such as 1/2x. If one rewrites this expression as 1 2 x and then interprets the division symbol as indicating multiplication by the reciprocal, this becomes

    Hence, with this interpretation we have that 1/2x is equal to (1/2)x, and not 1/(2x). However, there are examples, including in published literature, where implied multiplication is interpreted as having higher precedence than division, so that 1/2x equals 1/(2x), not (1/2)x.
    Last edited by Tranquil Suit; 11/08/2012 4:19pm at .

    (tab) Forum > Forum Actions > General Settings > in Thread Display Options > Number of Posts to Show Per Page: 40
  5. Mr. Machette is offline

    Senior Member

    Join Date
    Sep 2009
    Posts
    2,688

    Posted On:
    11/08/2012 4:23pm

    Join us... or die
     Style: FMA, Ego Warrior

    1
    Hell yeah! Hell no!
    Quote Originally Posted by goodlun View Post
    No problem what you are missing is the order of operation
    PEMDAS
    6/2*(2+1) Parentheses
    Exponents would be next but we don't have any
    6/2*(3) Multiplication
    6/6 Division
    Addition (we have none)
    Subtraction (we have none)
    1
    Thank you!

    I knew I was forgetting something in the order of operations!

    PEMDAS itself is simple enough to remember (havent thought about it in YEARS) but there's always those deceptively "easy" problems like this one designed to catch people who rush through their work. (An old academic weakness of mine that took a LOT of discipline to beat in school.)

    My mistake was doing the division of 6/2 before multiplying the 2(3). Classic quiz trick to see if the student is realy paying atention.
  6. Tranquil Suit is online now
    Tranquil Suit's Avatar

    On hiatus

    Join Date
    Jul 2009
    Posts
    3,442

    Posted On:
    11/08/2012 4:27pm

    supporting member
     Style: Getting fat.

    --
    Hell yeah! Hell no!
    Except you were right (cuz I sed so, and I should know, I'm an expert at multiplying 2 with 3)


    PEMDAS

    splits in

    P
    E
    MD
    AS

    (tab) Forum > Forum Actions > General Settings > in Thread Display Options > Number of Posts to Show Per Page: 40
  7. Mr. Machette is offline

    Senior Member

    Join Date
    Sep 2009
    Posts
    2,688

    Posted On:
    11/08/2012 4:33pm

    Join us... or die
     Style: FMA, Ego Warrior

    --
    Hell yeah! Hell no!
    Quote Originally Posted by Tranquil Suit View Post
    Except you were right (cuz I sed so, and I should know, I'm an expert at multiplying 2 with 3)


    PEMDAS

    splits in

    P
    E
    MD
    AS
    I see what you mean. With the division and multiplication priority being interchangeable depending on which country you learn math in the real fault is in how the problem itself is presented.

    solve for "x": 2(2+1)/6 = x

    Makes more sense and won't produce "correct errors".
    Last edited by Mr. Machette; 11/08/2012 4:38pm at .
  8. Tranquil Suit is online now
    Tranquil Suit's Avatar

    On hiatus

    Join Date
    Jul 2009
    Posts
    3,442

    Posted On:
    11/08/2012 4:41pm

    supporting member
     Style: Getting fat.

    1
    Hell yeah! Hell no!
    No, they have the same priority. So followup question is in what order do we compute operations of same priority, it is agreed to do it left to right, cause we write from left to right (suck it, Jews).


    Here's another bullshit question:

    16/8/2 = ?


    Basically, which division do you do first?





    from same wiki page:
    An expression like 1/2x is interpreted as 1/(2x) by TI-82, but as (1/2)x by TI-83.[8] While the first interpretation may be expected by some users, only the latter is in agreement with the standard rule that multiplication and division are of equal precedence, so 1/2x is read one divided by two and the answer multiplied by x.
    When the user is unsure how a calculator will interpret an expression, it is a good idea to use parentheses so there is no ambiguity.

    Say what you want about Wiki. Superficial information is done pretty well.
    Last edited by Tranquil Suit; 11/08/2012 4:47pm at .

    (tab) Forum > Forum Actions > General Settings > in Thread Display Options > Number of Posts to Show Per Page: 40
  9. goodlun is online now
    goodlun's Avatar

    Senior Member

    Join Date
    Jun 2008
    Location
    Ramona
    Posts
    4,616

    Posted On:
    11/08/2012 4:45pm

    Join us... or die
     Style: BJJ

    --
    Hell yeah! Hell no!
    Huh both my Ti-89 and wolfram|Alpha say the answer is 9
    http://www.wolframalpha.com/input/?i=6%2F2*%282%2B1%29
    I am willing to admit I very well may be wrong
  10. Rivington is offline
    Rivington's Avatar

    Senior Member

    Join Date
    Jun 2007
    Location
    East Bay, CA
    Posts
    4,733

    Posted On:
    11/08/2012 4:54pm

    supporting member
     Style: Taijiquan/Shuai-Chiao/BJJ

    4
    Hell yeah! Hell no!
    6/(2(2+1))
Page 21 of 27 FirstFirst ... 111718192021 22232425 ... LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Powered by vBulletin™© contact@vbulletin.com vBulletin Solutions, Inc. 2011 All rights reserved.