Abel can complete a work in 10 days, Ben in 12 days…

Abel can complete a work in 10 days, Ben in 12 days and Carla in 15 days. All of them began the work together, but Abel had to leave after 3 days and Ben 4 days before the completion of the work. How long did the work last?

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #11203