Question

A person travels by car from one city to another with different constant speeds between the cities. She drives 30 min at 80 km/hr, 12 min at 100 km/hr and 45 min at 40 km/hr. Determine the average speed for the trip and determine the distance between the initial and final cities along the trip.

Answer 1

To find the average speed for the trip, calculate the total distance traveled and the total time taken. The average speed is approximately 62.07 km/h. The distance between the initial and final cities along the trip is 90 km.

Step-by-step explanation:

To find the average speed for the trip, we need to calculate the total distance traveled and the total time taken. First, convert the times into hours: 30 minutes is 0.5 hours, 12 minutes is 0.2 hours, and 45 minutes is 0.75 hours.

Next, calculate the distances traveled at each speed: 0.5 hours at 80 km/hr is 40 km, 0.2 hours at 100 km/hr is 20 km, and 0.75 hours at 40 km/hr is 30 km.

The total distance traveled is 40 km + 20 km + 30 km = 90 km. The total time taken is 0.5 hours + 0.2 hours + 0.75 hours = 1.45 hours.

Finally, divide the total distance by the total time to find the average speed: 90 km / 1.45 hours ≈ 62.07 km/h.

The distance between the initial and final cities along the trip is 90 km.