A,B,C can do a piece of work in 11days, 20days and 55days…

A,B,C can do a piece of work in 11days, 20days and 55days respectively, working alone. How soon can the work be done if A is assisted by B and C on alternate days?

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 #72766