The speed of car is S km/hr running on the road beside a railway track. If the speed of the train is (S + 144) km/hr and car is D meter distance ahead of the engine of train. The train will pass the car in 21 seconds. If the speed of the car is 60 km/hr and the speed of the train is (S + 110) km/hr. The car is (D – 240) meter distance ahead of the engine of the train and the train will pass the car in 20 seconds. The length of the train is (D + 160) m. Then, what is the value of S?