A car travels from City A to City B at an average speed of 60 mph and returns at an average speed of 40 mph. What is the average speed of the car for the entire trip?
Correct: A
To find the average speed for the entire trip when the distances traveled at different speeds are the same, we use the formula for average speed = (2 * speed1 * speed2) / (speed1 + speed2). Thus, the average speed = (2 * 60 * 40) / (60 + 40) = 4800 / 100 = 48 mph.