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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