Boojho walks to his school which is at 4.5 km from his home in 120 min. On reaching, he finds that the school is closed and comes back by a bicycle with his friend and reaches home in 60 min. His average speed in km/h is?
Answers
The average speed of Boojho is 7.2km/hour.
Explanation:
The formula for finding average speed is = Total distance/Total speed
Total distance = 3+3 = 6km ( up and down)
Total time = 30 +20 minutes = 50/60 hours ( up and down)
So, the average speed is =( 6*60)/50 = 36/5 = 7.2 km/hour( or 2m /sec).
The average speed of Boojho is 7.2km/hour.
ANSWER
Boojho walks to his school which is at a distance of 3 km from his home in 30 min. On reaching, he finds that the school is closed and comes back by a bicycle with his friend and reaches home in 20 min. His average speed in km/h.
Solution
From home to school distance is given as 3 km time taken is 30 min = (30/60) hour = 0.5 hour
And in returning from school to home time taken = 20 min = (20/60) hour = 0.33 hour
average speed = Total distance / time taken
= (3 + 3)/(0.5 + 0.33) km/h
= 7.2 km/h