In an 800km race one runner runs at a steady 113kmh and

Question

Problem: In an 8.00km race, one runner runs at a steady 11.3km/h and another runs at 14.5km/h.

Part A: How far from the finish line is the slower runner when the faster runner finishes the race?

I don't know how to get that answer for the above problem. Please help! Thanks.