Question

A bus traveling along a straight highway covers one-
third of the total distance between two places with a
velocity 20 kmh. The remaining part of the dis-
tance was covered with a velocity of 30 km h + for
the first half of the remaining time and with velocity
50 km h-t for the next half of the time. Find the
average velocity of the bus for its whole journey.​

Answer 1

Answer:

30 km/hr

Explanation:

As  average velocity = total displacement / total time taken

Now let total displacement is "x"

now as given in the question it covers first one third journey with 20km/hr.

now let assume it cover remaining "y" distance for first half of remaining time and "z" for next half of remaining time.

Also it is given in question that it cover distance "y" and "z" in equal time interval. So from this we get z=5y/3

Now, x/3+y+z = x

so, x/3+ y+5y/3 = x , from here we get y=x/4 and z=5x/12

Now, total time = (x/3)(1/20) + (x/4)(1/30) + (5x/12)(1/50)

so by using formula of average velocity

we get average velocity = 30 km/hr