If a cyclist travels at a speed of 15 km/h for 1 hour and then at 20 km/h for 2 hours, what is the average speed for the entire journey? (2022)
Practice Questions
1 question
Q1
If a cyclist travels at a speed of 15 km/h for 1 hour and then at 20 km/h for 2 hours, what is the average speed for the entire journey? (2022)
17 km/h
18 km/h
19 km/h
20 km/h
Total distance = 15 km + 40 km = 55 km; Total time = 1 h + 2 h = 3 h; Average speed = Total distance / Total time = 55 km / 3 h = 18.33 km/h.
Questions & Step-by-step Solutions
1 item
Q
Q: If a cyclist travels at a speed of 15 km/h for 1 hour and then at 20 km/h for 2 hours, what is the average speed for the entire journey? (2022)
Solution: Total distance = 15 km + 40 km = 55 km; Total time = 1 h + 2 h = 3 h; Average speed = Total distance / Total time = 55 km / 3 h = 18.33 km/h.
Steps: 5
Step 1: Calculate the distance traveled at the first speed. The cyclist travels at 15 km/h for 1 hour. Distance = speed × time = 15 km/h × 1 h = 15 km.
Step 2: Calculate the distance traveled at the second speed. The cyclist travels at 20 km/h for 2 hours. Distance = speed × time = 20 km/h × 2 h = 40 km.
Step 3: Add the distances from Step 1 and Step 2 to find the total distance. Total distance = 15 km + 40 km = 55 km.
Step 4: Calculate the total time taken for the journey. Total time = 1 h + 2 h = 3 h.
Step 5: Calculate the average speed using the formula: Average speed = Total distance / Total time. Average speed = 55 km / 3 h = 18.33 km/h.
