One car left a city at 200 PM and traveled at an average spe

One car left a city at 2:00 PM and traveled at an average speed of 40 miles per hour. A second car left at 4:00 PM, traveled the same route and overtook the first car at 9:00 PM. What was the average speed in miles per hour of the second car?

Solution

D=RT
D=40*7 FOR THE FIRST CAR.
D=R5 FOR THE SECOND CAR.
40*7=5R
5R=280
R=280/5
R=56 MPH. IS THE SPEED OF THE SECOND CAR.