Question

please answer this question...please ..

Answer 1

let the length of the journey be x

so,
in distance,
first part=x/3
second part=x/3m
third part=x/3m

in time,
1st=x/(3×2)=x/6s
2nd=x/(3×3)=x/9s
3rd=x/(3×6)=x/18s

so,
avg velocity
=(x/3+x/3+x/3)/(x/6+x/9+x/18)
=(3x/3)/[(3x+2x+x)/18]
=x/(6x/18)
=x/(x/3)
=3m/s