2022 Waseda Junior High School "Geometry"

Problem
In the parallelogram ABCD shown in the figure, BE : EC = 5 : 2 and CF : FD = 2 : 3. Also, the areas of triangle ADF and triangle ADG are both 210 cm². What is the area of the shaded region in cm²?

※Information regarding use
For publication on the web, some content of the problems may have been edited for the purpose of readability or standardization of expression. Please refer to the official problems for accurate information.

Solution method