Joe covers a distance of 324 miles between two cities in 18 hours. Approximate the average distance covered by Joe in one hour.
Jasleen covered a distance of 1560 miles between city P and city Q taking a total of 10 hours. If part of the distance was covered at 120 miles per hour speed and the balance at 160 miles per hour speed, how many hours did she travel at 120 miles per hour?