Question

A bus covers a distance of first 50 km in 40 minutes, next 50 km at a speed of 2 km per minute and the next 30 km at a speed of 1.0 km per minute. What is its average speed during the entire journey?

Accepted Answer

C. Total distance = $50 + 50 + 30 = 130$ km. Time 1 = 40 minutes. Time 2 = $\frac{50}{2} = 25$ minutes. Time 3 = $\frac{30}{1.0} = 30$ minutes. Total time = $40 + 25 + 30 = 95$ minutes = $\frac{95}{60}$ hours. Average speed = $\frac{	ext{Total distance}}{	ext{Total time}} = \frac{130}{95/60} = \frac{130 	imes 60}{95} \approx 82.1$ kmph.

Average speed of a bus

Explanation

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