Position vectors of the vertices of the △ABC are a,b and c. ∴ Centroid of △ABC is
a+b+c
3
We know, when through the vertices, lines are drawn parallel to the sides to form a new triangle, then obtained such triangle will have the same centroid as the original triangle, which is also clear from the above graphical figure. ∴ Centroid of ∆A′B′C′ is