Results 1 to 4 of 4

Math Help - ratio prob

  1. #1
    Member GAdams's Avatar
    Joined
    Apr 2007
    Posts
    171
    Awards
    1

    ratio prob

    Due to illness a man's weight increases each year in the ratio 10:11
    He starts at 13 stones
    How heavy will he be at the end of the third year?

    I'm not sure how to tackle this, I thought...

    10: 11 as a percentage is 91% and after 3 years, 91 stones....? Got to be wrong.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    -1
    e^(i*pi)'s Avatar
    Joined
    Feb 2009
    From
    West Midlands, England
    Posts
    3,053
    Thanks
    1
    Quote Originally Posted by GAdams View Post
    Due to illness a man's weight increases each year in the ratio 10:11
    He starts at 13 stones
    How heavy will he be at the end of the third year?

    I'm not sure how to tackle this, I thought...

    10: 11 as a percentage is 91% and after 3 years, 91 stones....? Got to be wrong.
    Use the compound interest formula.

    A(t) = A_0\left(1+\frac{11}{10}\right)^t

    A_0 = 13

    t = 3
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member GAdams's Avatar
    Joined
    Apr 2007
    Posts
    171
    Awards
    1
    Quote Originally Posted by e^(i*pi) View Post
    Use the compound interest formula.

    A(t) = A_0\left(1+\frac{11}{10}\right)^t

    A_0 = 13

    t = 3
    That's basically what i did:

    13 x (1.91)^3 = 90.6 stones (1 dp)

    I just thought I had gone wrong....90 stones is over 500 kg!
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Member GAdams's Avatar
    Joined
    Apr 2007
    Posts
    171
    Awards
    1
    Quote Originally Posted by e^(i*pi) View Post
    Use the compound interest formula.

    A(t) = A_0\left(1+\frac{11}{10}\right)^t

    A_0 = 13

    t = 3

    Hmm....why 11/10 and not 10/11?
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 2
    Last Post: April 12th 2011, 11:13 AM
  2. Ratio for curve and point-ratio form
    Posted in the Algebra Forum
    Replies: 4
    Last Post: January 11th 2010, 01:07 AM
  3. Finding n given the ratio of nCr to another ratio
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: October 5th 2009, 08:03 PM
  4. UDD prob
    Posted in the Business Math Forum
    Replies: 1
    Last Post: May 10th 2009, 11:25 AM
  5. MOre Prob
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: May 12th 2008, 11:01 AM

Search Tags


/mathhelpforum @mathhelpforum