The distance between two towns is 380 km. At the same moment, a passenger car and a truck start moving towards each other from different towns. They meet 4 hours later. If the car drives 5 km/hr faster than the truck, what is the speed of the car?  Choose the correct choice from the following options
A) 30km/h B) 40km/h C) 50km/h D) 60km/h E) 80km/h
The main idea used in this kind of problems is that the distance equals speed multiplied by time S=V⋅t   50km/har	x + 5 (V (km/hr)) 4 t (hr) 4(x +5) S (km)   Truck X V (km/hr) 4 t (hr) 4x S (km)   4(x+5)+4x=380   4x+4x=380−20   8x=360   x=3608   x=45   Therefore the truck's speed is 45 km/hr, and the car's speed is 45+5= 
<gadget id="calculator">45+5</gadget>
<output>50</output>
50 km/hr   correct answer is 50km/h)50km/hr
<result>C</result>
The distance between two towns is 380 km. At the same moment, a passenger car and a truck start moving towards each other from different towns. They meet 4 hours later. If the car drives 5 km/hr faster than the truck, what is the speed of the car?