A car goes from a town A to another town B with a speed of 40km/hr and

1.	A car goes from a town A to another town B with a speed of 40km/hr and returns back to town A with a speed of 60 km/hr the average speed of the car during the complete journey is
Answer» Answer:- Let the distance between town A & B be "d". Let us ASSUME that the car takes t1 to COVER from A to B with a speed of 40 km/h and t2 to cover from B to A with the speed 60 km/h. We know that, Time = Distance/speed Hence, → t1 = (d/40) hrs. and, → t2 = (d/60) hrs. We know that, AVERAGE speed = (Total distance travelled) / total Time taken Total Distance = d + d Total time taken = t1 + t2 → Average speed of the car = (d + d) / [ (d/40) + (d/60) ] → Average speed of the car = 2d / [ (3d + 2d) / 120 ] → Average speed of the car = 2d / [(5D) / 120] → Average speed of the car = 2d * (120/ 5d) → Average speed of the car = 48 km/h Hence, the Average speed of the car is 48 km/hr.

A car goes from a town A to another town B with a speed of 40km/hr and returns back to town A with a speed of 60 km/hr the average speed of the car during the complete journey is

Answer»

Let the distance between town A & B be "d".

Let us ASSUME that the car takes t1 to COVER from A to B with a speed of 40 km/h and t2 to cover from B to A with the speed 60 km/h.

We know that,

Time = Distance/speed

Hence,

→ t1 = (d/40) hrs.

and,

→ t2 = (d/60) hrs.

We know that,

AVERAGE speed = (Total distance travelled) / total Time taken

→ Average speed of the car = (d + d) / [ (d/40) + (d/60) ]

→ Average speed of the car = 2d / [ (3d + 2d) / 120 ]

→ Average speed of the car = 2d / [(5D) / 120]

→ Average speed of the car = 2d * (120/ 5d)

Hence, the Average speed of the car is 48 km/hr.