Question 182486
Since, distance = speed * time, and we know that the distances are equal, we can say,

Speed(P)*time(P)=Speed(F)*time(F)

From your givens, we know that:

time(P) = 1 hr (3 hr - 2 hr)

time(F) = 3 hr

We also know that,

Speed(P) = Speed(F) + 20


So, back to the first equation, we can now say:

[Speed(F)+20]*[1hr]=[Speed(F)]*[3hr]

I will use the notation F and P for speeds.

F+20=3F ... 2F = 20... F = 10

P = F + 20 = 10 + 20 = 30


Speed of passenger train = 30 mph, freight train = 10 mph