Question

A car is moving on a straight road covers one third of the distance with a speed of 20 km per hour and the rest with a speed of 60 km per hour the average speed of the car is what

Answer 1

Answer:

36 km/h

Explanation:

We know that =total distance travelled/total time taken.

Total distance be 'S'.so acc. To question

S/3 +2S/3=S.

Now for ist one third , consider time taken is 't' so now speed × time = distance so 20×t=S/3 by solving it we find that t=S/60 h and in the similiar way we find time dor second 2S/3 journey which come t=S/90 hour.

Now put these values of time in equation of average speed

=S/S/60+S/90 and then answer is 36 km/h