A car travels from point A to B at a speed of 60 km/hr and returns back to…
A car travels from point A to B at a speed of 60 km/hr and returns back to point A at a speed of 40 km/hr. What is the average speed of the car during the whole journey?
Answer: A. 48 km/hr — To find the average speed for the entire journey, we use the formula for average speed, which is total distance divided by total time. The distance traveled…
- A.
48 km/hr
- B.
50 km/hr
- C.
24 km/hr
- D.
49 km/hr
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Show answer & explanation
Correct answer: A
To find the average speed for the entire journey, we use the formula for average speed, which is total distance divided by total time. The distance traveled is the same for both legs of the journey, so let's call that distance "d".
Time to go from A to B = d / 60 hours
Time to return from B to A = d / 40 hours
Total time for the journey = d/60 + d/40 = (2d + 3d) / 120 = 5d / 120 = d / 24 hours
Total distance = 2d (since the car travels to B and then returns to A)
So, the average speed = (2d) / (d/24) = 2d × (24/d) = 48 km/hr.