Results 1 to 5 of 5

Math Help - Long division answer diffrent to calculator

  1. #1
    Newbie
    Joined
    Nov 2008
    Posts
    2

    Long division answer diffrent to calculator

    Hi guys,

    I've got a bit of a problem with my long division - I was hoping you could help me with please. I keep getting a slight variation between my results on paper and the one I get from the calculator.

    Question: If a/c flies 764 miles in 78 mins how fast is it moving?

    S=D/t

    So the equation I'd use is

    S = (764 / 78) x 60 (to convert the minutes to hours).

    The result I got from long division is 578MPH...
    However using a calculator, the answer I got was more like 587MPH..

    I've noticed this problem with pretty much any equation I do using long division.. The answer is always slightly different to that of the calculator mainly after the decimal point.

    Before the x60 conversion, the decimal I had from long division (764 / 78 = 9.62) but the calculator's answer was more like 9.79.. which seems to make all the diffrence.

    No matter what I do, I cant seem to replicate this answer using simple long division.

    Am I doing this all wrong?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Banned
    Joined
    Aug 2008
    Posts
    530
    Quote Originally Posted by EvoUK View Post
    Hi guys,

    I've got a bit of a problem with my long division - I was hoping you could help me with please. I keep getting a slight variation between my results on paper and the one I get from the calculator.

    Question: If a/c flies 764 miles in 78 mins how fast is it moving?

    S=D/t

    So the equation I'd use is

    S = (764 / 78) x 60 (to convert the minutes to hours).

    The result I got from long division is 578MPH...
    However using a calculator, the answer I got was more like 587MPH..

    I've noticed this problem with pretty much any equation I do using long division.. The answer is always slightly different to that of the calculator mainly after the decimal point.

    Before the x60 conversion, the decimal I had from long division (764 / 78 = 9.62) but the calculator's answer was more like 9.79.. which seems to make all the diffrence.

    No matter what I do, I cant seem to replicate this answer using simple long division.

    Am I doing this all wrong?
    correct answer is 587.6923 miles/hr
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Nov 2008
    Posts
    2
    Can you replicate that answer using long division alone?
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Banned
    Joined
    Aug 2008
    Posts
    530
    Quote Originally Posted by EvoUK View Post
    Can you replicate that answer using long division alone?
     = \left( {764 \div 78} \right) \times 60 \hfill \\

    {\text{Long division is}} \hfill \\

    78{\text{ }}\overline {){\text{ }}764{\text{ }}(} {\text{ }}9.79487179 \hfill \\

    {\text{            }}\underline {{\text{ 702 }}}  \hfill \\

    {\text{          620}} \hfill \\

    {\text{       }}\underline {{\text{ 546 }}}  \hfill \\

     {\text{            740}} \hfill \\

    {\text{          }}\underline {{\text{  702  }}}  \hfill \\

    {\text{              380}} \hfill \\

    {\text{            }}\underline {{\text{  312  }}}  \hfill \\

    {\text{                 680}} \hfill \\

    {\text{               }}\underline {{\text{  624  }}}  \hfill \\

    {\text{                   560}} \hfill \\

    {\text{       }}\underline {{\text{ 546 }}}  \hfill \\

    {\text{                     140}} \hfill \\

    {\text{                   }}\underline {{\text{    78  }}}  \hfill \\

    {\text{                       620}} \hfill \\

    {\text{                     }}\underline {{\text{  546  }}}  \hfill \\

    {\text{                         740}} \hfill \\

    {\text{                       }}\underline {{\text{  702  }}}  \hfill \\

    {\text{                            38}} \hfill \\

    {\text{Now,}} \hfill \\

    9.79487179 \times 60 = 587.6923074 \simeq 587.69 \hfill \\ <br />
    Last edited by Shyam; November 15th 2008 at 09:45 AM.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    MHF Contributor

    Joined
    Apr 2005
    Posts
    15,705
    Thanks
    1470
    Yes, and that is what the calculator gave you! You said before:
    The result I got from long division is 578MPH...
    Obviously, you divided incorrectly the first time.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. long division
    Posted in the Algebra Forum
    Replies: 4
    Last Post: March 27th 2011, 12:31 PM
  2. Polynomial Long Division Calculator
    Posted in the Math Software Forum
    Replies: 2
    Last Post: November 4th 2010, 06:41 PM
  3. Long division
    Posted in the Algebra Forum
    Replies: 2
    Last Post: October 15th 2008, 11:44 AM
  4. Long Division
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: August 20th 2008, 03:55 PM
  5. Long Division
    Posted in the Algebra Forum
    Replies: 1
    Last Post: January 31st 2008, 01:56 PM

Search Tags


/mathhelpforum @mathhelpforum