v1 = 1/14 miles per min the average speed of Roger
v2 = 1/12 miles per min the average speed of Jeff
t = the time in minutes that Jeff runs before catches up to Roger
t + 1 = the time in minutes that Roger runs before Jess catches up with him
since the both run the same distance and distance = speed*time we have
v1*(t + 1) = v2*t
(1/14)(t + 1) = (1/12)*t
by solving we find
t = 6 min
the distance each of them runs is v2*t = (1/12)*6 = 1/2 mile
