A Freight train is traveling 30 miles per hour. An automobile starts out from the same place 1 hour later and overtakes the train in 3 hours. What was the rate of the automobile.

40 I believe because the space of the auto mobile catching up to the train is 4 hours. 4 times 30 is 120 miles so u need to figure out a number that can reach 120 in three hours. 3 times 40 is 120