2005 AMC 10B Problems/Problem 23
Problem
In trapezoid we have
parallel to
,
as the midpoint of
, and
as the midpoint of
. The area of
is twice the area of
. What is
?
Solution
The length of is the arithmetic mean of the two parallel bases. Since the base EF is shared between the two smaller trapezoids, you want {boxed$AB/DC = 2$}.