Math help please. 2 cars were traveling.?

Joe and Cindy are in a race. They're racing to kamloops which is 150km away. Joe is traveling 60km/h and cindy is driving 50km/h. 70k in the race joes car has some trouble and needs to drive the last 80k at 40km/h. At what point of the race do they meet. Please show work so i understand