As shown in the diagram, $PQ/QR=1/3.$ Find $[PAB]/[QAB].$

[PAB] means the area of triangle PAB. I'm asking for a ratio of the areas of the two triangles.

Thank you to whoever solves it! :)

Hint: quadrilateral ABQP can have a shape like a kite.

By mass points, [PAB]/[QAB] = 3/2.