A is twice as fast as B

A is twice as fast as B. If B alone can do a piece of work in 10 days, in what time can A and B together complete the work?

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 #43013