Thats the exact answer I got. So I think I can assume that we are correct. The original poster resposted this with a slight modification where the last runner runs at a pace of 10 mph. The only thing this changes is the place you finish.
There are 12 different colors. Thay all appear to be relatively close but there are 3 different greens, 3 different blues, 3 different tans and 3 different oranges. Im not sure if this will help anyone but the author of this brain teaser said that color mattered