Results 1 to 2 of 2

Math Help - Similar shapes question

  1. #1
    Richie92
    Guest

    Similar shapes question

    I'm stuck on the following question :

    An A3 sheet of paper can be cut into 2 sheets of A4.
    The A3 and A4 sheets are mathmatically similar.

    Find the scale factor: (long side of A3 sheet) ie. x
    (long side of A4 sheet) y

    I do actually know that the correct answer to this question is the square root of 2 but I need to show how this has been worked out and I don't have a clue.

    Thanks
    Richie
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member

    Joined
    May 2006
    From
    Lexington, MA (USA)
    Posts
    11,547
    Thanks
    539
    Hello, Richie92!

    An A3 sheet of paper can be cut into 2 sheets of A4.
    The A3 and A4 sheets are mathmatically similar.

    Find the scale factor: .x/y
    . . where x = long side of A3, y = long side of A4.

    A3 is an x-by-y rectangle.
    Code:
                    x
          * - - - - - - - - - *
          |                   |
          |                   |
        y |        A3         | y
          |                   |
          |                   |
          * - - - - - - - - - *
                    x

    It is bisected into two rectangles where A3 ~ A4.
    Code:
              x
          * - - - - *
          |         |
          |         |
        y |   A4    |y
          |         |
          |         |
          * - - - - *
              x

    . . . . . . . . x . . . y . . . . .x
    We have: . ---- .= .-- . . --- .= .2
    . . . . . - - - .y . . - .x . . . . .y


    . . . . - - . . .x . . . . _
    Therefore: . -- .= .√2
    . . . . - - . . .y

    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: December 22nd 2011, 12:12 AM
  2. Similar shapes (Volume and surface area)
    Posted in the Geometry Forum
    Replies: 5
    Last Post: March 26th 2011, 05:56 AM
  3. volume of Frustum using similar shapes method
    Posted in the Geometry Forum
    Replies: 2
    Last Post: November 13th 2010, 01:37 PM
  4. Calculus and shapes crossover question! Help!!
    Posted in the Calculus Forum
    Replies: 8
    Last Post: December 27th 2006, 06:25 AM
  5. Replies: 1
    Last Post: August 17th 2006, 05:54 AM

Search Tags


/mathhelpforum @mathhelpforum