Difference between revisions of "2006 AIME I Problems/Problem 7"

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== Solution ==
 
== Solution ==
 
{{solution}}
 
{{solution}}
 +
Let:
 +
  The set of parallel lines...
 +
      perpendicular to x-axis &
 +
      cross x-axis at 0, 1, 2...
  
 +
  The base of area A is at x = 1.
  
 +
  One side of the angle be the x-axis.
 +
 +
  The other side be y = x-h...
 +
      as point of the angle isn't on
 +
      parallel lines
 +
 +
Then...
 +
 +
Area C / Area B = 11 / 5
 +
= [.5(5-h)^2 - .5(4-h)^2] / [.5(3-h)^2 - .5(2-h)^2]
 +
Thus h = 5/6
 +
 +
By similar method, D/A seems to be 408.
  
 
== See also ==
 
== See also ==

Revision as of 18:21, 11 March 2007

Problem

An angle is drawn on a set of equally spaced parallel lines as shown. The ratio of the area of shaded region $\mathcal{C}$ to the area of shaded region $\mathcal{B}$ is 11/5. Find the ratio of shaded region $\mathcal{D}$ to the area of shaded region $\mathcal{A}.$



Solution

This problem needs a solution. If you have a solution for it, please help us out by adding it. Let:

  The set of parallel lines...
     perpendicular to x-axis &
     cross x-axis at 0, 1, 2...
  The base of area A is at x = 1.
  One side of the angle be the x-axis.
  The other side be y = x-h...
     as point of the angle isn't on
     parallel lines

Then...

Area C / Area B = 11 / 5 = [.5(5-h)^2 - .5(4-h)^2] / [.5(3-h)^2 - .5(2-h)^2] Thus h = 5/6

By similar method, D/A seems to be 408.

See also