In a 1000 m race Usha beats Shiny by 50 m

In a 1000 m race Usha beats Shiny by 50 m. In the same race, by what time margin Shiny beat Mercy. who runs at 4 m/s ?

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #65698