Area of Triangles · Superchallenge problem

Triangle $ABC$ has an area of $90$ square cm. Point $D$ is on side $AB$ with $AD$ one third of $AB$. Point $E$ is on side $AC$ with $AE$ two thirds of $AC$. Cutting along $DE$ splits the triangle into triangle $ADE$ and a four-sided piece $DBCE$. What is the area of $DBCE$, in square centimeters?