Two riders are racing. When A has 6 km to go he is told that B is 4 minutes ahead of him and travelling a constant speed. A speeds up to a rate 2 km/hr faster than B to try to catch him. When A finishes he learns that he lost by 2 minutes.
What was A speed over the last 6 km? Both riders had a constant speed.
I would love some help on this one. I can't get started.