Question

A train travels a distance of 60km with a uniform speed of 60km/h. It travels another 50 km with a speed of 80km per hour
Calculate the average speed of the train​

Answer 1

Total distance = (60+50)km = 110km

Total time = 60/60h + 50/80h

=13/8h

Average Speed

=67.69(approx.)

Answer 2

Solution:

It is given that a train travels a distance of 60km with a uniform speed of 60km/h. It travels another 50 km with a speed of 80km per hour.

Find the time taken by train in both condition:

Case I :

• Time = Distance ÷ Speed
• Time = 60 ÷ 60 hr
• Time = 1 hr

Case II :

• Time = Distance ÷ Speed
• Time = 50 ÷ 80
• Time = ⅝ hr

Find the average speed of the train:

Average Speed = Total Distance ÷ Total Time

∵Average Speed = ∆D/∆T

• Average Speed = (60 + 50) km /( 1 + ⅝) hr
• Average Speed = 110 ÷ 13/8
• Average Speed = 110 × 8 / 13
• Average Speed = 67.7km/hr

Therefore, Required Average Speed of the train is 67.7 km/hr.