P is three times as old as Q

P is three times as old as Q. In 9 years, P will be twice as old as Q. How old was P three years ago?

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #9079