Answer :
9514 1404 393
Answer:
the average speed is 50 10/13 mph
Step-by-step explanation:
The relationship between time, speed, and distance is ...
distance = speed × time
The distance traveled in the first part of the car's journey is ...
(45 mi/h)(2/3 h) = 30 mi
The distance traveled in the second part of the car's journey is ...
(60 mi/h)(25/60 h) = 25 mi
Then the total distance is 30 mi +25 mi = 55 mi.
The total time is ...
40 min +25 min = 65 min = 65/60 h = 13/12 h
The average speed for the trip is ...
speed = distance/time = (55 mi)/(13/12 h) = 660/13 mi/h = 50 10/13 mi/h
The average speed of the journey is 50 10/13 mi/h, just over 50 mi/h.