The speed of a train is 3 times that of a car and 1.5 times of a steamer. A person travelled x km by steamer, 3.75x km by train and x/2 km by car. If the speed of the car is 40 km/h and total time taken by him is \(4\frac{1}{2}\) hours, then the total distance travelled by him in three modes is:

• A. 450 km
• B. 520 km
• C. 480 km
• D. 420 km