John, Mac and Tonny together can do a work in 20 days

John, Mac and Tonny together can do a work in 20 days. John alone can do the work in 80 days and Mac alone can do the same work in 70 days. Find in what time Tonny alone can do that work?

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #73539