The distance between two cities is 360 km. At the same moment a car and a truck start moving towards each other from different cities. They meet 4 hours later. If the car drives 10 km/hr. faster than the truck. Find the ratio between the speed of the car and the truck?

Let truck's speed be x km/hr. Then car's speed is (x+10) km/hr. They travel towards each other, so their combined speed is x + (x+10) = 2x + 10. In 4 hours, they cover 360 km together. So 4(2x + 10) = 360, which gives 2x + 10 = 90, so 2x = 80 and x = 40. Therefore, truck's speed is 40 km/hr and car's speed is 50 km/hr. The ratio car:truck = 50:40 = 5:4.