△ ABC is divided into five triangles of equal area.
Find AD:DE:EC.
3:4:8
As △ABD : △DBC = 1 : 4, AD : DE = 1 : 4.
As △DFE : △EFC = 1 : 2, DE : EC = 1 : 2.
DE = 4 × 1/(1+2) = 4/3
EC = 4/3 × 2 = 8/3
Therefore, AD : DE : EC = 1 : 4/3 : 8/3 = 3 : 4 : 8.
Mt.Fuji & Sakura