ABCD is a parallelogram, and DE = EC.
What is the ratio of the area of triangle ADE to the area of the parallelogram?
A. 1:2
B. 1:3
C. 1:4
D. 1:5
E. 2:5
The area of triangle ADE equals the area of triangle AEC, since they have the same base and altitude. The area of triangle ABC equals that of triangle ADC, since the diagonal of a parallelogram divides it equally.