k = 1, 2, and 3, let B be the point on the boundary of AA₁ A2 A3
located 1/3 unit away from A, in the clockwise direction and let Ck
be the point on the boundary of AA₁ A2 A3 located 1/3 unit away from
Ak in the counterclockwise direction. What fraction of the area of
AA₁A2A3 is the area of the intersection of AB₁ B2 B3 and AC1C2C3?
Express your answer as a fraction in simplest form.
Fig: 1