In a trapezium ABCD, AB is parallel to DC, AB = 3*DC, and the diagonals of the trapezium intersect at O. The ratio of the area of ∆OCD to the area of ∆OAB is:	Choose the correct choice from the following answers
A) 1:9
B) 1:3
C) 3:1
D) 1:10
E) Cannot be determined
triangles are similar , so ratio will be 1:9   1:9
<result>A</result>
In a trapezium ABCD, AB is parallel to DC, AB = 3*DC, and the diagonals of the trapezium intersect at O. The ratio of the area of ∆OCD to the area of ∆OAB is: