Results 1 to 2 of 2

Math Help - maybe simple percentage question! Help!

  1. #1
    christos
    Guest

    maybe simple percentage question! Help!

    Hello,

    I need help to make 0.85p into 0.31p and have the percentage shown, so that 85p turns into 31p automatically, what would be the best way to achieve this on a calculator?

    Everytime I try I just have to guess, like 85 / 2.7(guess) = 31.481481
    then I would do 100 - 31 = 69%

    Is this the only way, is there a quicker method?

    Thank you
    Regards
    Chris
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member

    Joined
    May 2006
    From
    Lexington, MA (USA)
    Posts
    11,807
    Thanks
    697
    Hello, Chris!

    The question is not clear . . .


    I need help to make 0.85p into 0.31p and have the percentage shown,
    so that 85p turns into 31p automatically.
    What would be the best way to achieve this on a calculator?
    I'll take a guess . . .


    To change 0.85 into 0.31, we will multiply by some percent.

    Let x = the percent.

    Then we have: . 0.85x \:=\:0.31

    It follows that: . x \:=\:\frac{0.31}{0.85} \:=\:0.364705882

    Therefore: . x\:\approx\:36.5\%

    ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

    Check

    36.5\% \times 0.85 \;=\;(0.365)(0.85) \;=\;0.31025 . . . close enough!

    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Simple percentage problem
    Posted in the Algebra Forum
    Replies: 1
    Last Post: March 3rd 2011, 06:20 PM
  2. Simple Percentage Logic
    Posted in the Math Puzzles Forum
    Replies: 11
    Last Post: September 29th 2010, 12:52 PM
  3. Percentage question #5
    Posted in the Algebra Forum
    Replies: 2
    Last Post: October 21st 2009, 07:48 PM
  4. Simple calculation of difference in percentage
    Posted in the Statistics Forum
    Replies: 2
    Last Post: July 30th 2009, 01:34 AM
  5. Percentage question:
    Posted in the Statistics Forum
    Replies: 2
    Last Post: May 19th 2007, 09:55 PM

Search Tags


/mathhelpforum @mathhelpforum