Question

A car moving on a straight road covers one third of the distance with 20 km/h and the rest with 60 km/h. The average speed of the car is

Answer 1

Answer :

Speed of car when it travelled the half distance was 20 km/h and the rest with 60 km/h.

So, A.T.Q

➺ Average Speed = Total Distance/Total Speed

Assuming the total distance to be 3x.

Time taken by the car to cover one-third of the distance = x/20

Time taken to cover two-thirds of the distance by the car = 2x/60

= x/30 Total time taken by the car

= x/20 + x/30 equals to 5x/60 which is x/12

Average speed obtained = (Total distance travelled)/(Total time taken)

= (3x)/(x/12) = 36 kilometre/hour

$\rule{200}{2}$