A car travels from point A to point B. The average speed of the car is 60 km/hr and it travels the first half of the trip at a speed of 48 km/hr. What is the speed of the car in the second half of the trip?
Choose the correct choice
A) 72  B) 75  C) 80  D) 84  E) 90
Let D be the distance and let V be the speed in the second half.   The total time = T1 + T2   D/60 = D/96 + (D/2) / V   8D/480 - 5D/480 = (D/2) / V   D/160 = D/2V and so V = 80 km/hr   The answer is 80.
<result>C</result>
A car travels from point A to point B. The average speed of the car is 60 km/hr and it travels the first half of the trip at a speed of 48 km/hr. What is the speed of the car in the second half of the trip?