Question

b).
A car travels the first 20 km of a journey at a uniform speed of 40
kmhr 1 and the next 20 km at 50 kmhr 1.Calculate the average
speed of the car?​

Answer 1

Answer:

40+50/20 =90/20 = 9/2 answer is 9/2

Answer 2

Answer:

Average speed = Total distance/Total time

Therefore, first we should find time .

time = distance / speed

time= 20+ 20 / 40+ 50

ie. 40/ 90

or 4/ 9 sec

Then , average speed = Total distance / Total time

= 40/ (4/9)

= 90 km/ hr.