Question

Rahul and his friends left for Guptipara by bus at 3 p.m. The bus travelled at an average speed of 45 km/h for the first hour and then the group took a break for 30 minutes. After the break,the bus travelled at 30 km/h for only 15 minutes when it had to stop because of a punctured tyre.After getting the tyre repaired, the bus travelled at 50 km/h to finally reach Guptipara at 6.45 p.m.
What was the average speed of the bus in completing
the journey of 90 km?
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Answer 1

Answer:

Average Speed = Total distance covered/Total time taken

$= \frac{90km}{6.45p.m. - 3p.m.} = \frac{90km}{3h \: 45min}$

Now,

$\frac{45min}{1hour} = \frac{45min}{60min} = 0.75hours$

Thus, Average speed

$= \frac{90km}{3.75h} = 24km \: per \: hour$