A body has speed V,2V, and 3V in the first 1/3 of distance S, seconds 1/3 of S and third 1/3 of S respectively. Its average speed will be:

Average speed =$\frac{Total dis\tan ce}{Time taken}$

Time Taken in covering first $\frac{1}{3}$​ distance of s,

t₁​=$\frac{S/3}{V}$

Time Taken in covering second $\frac{1}{3}$​ distance of s,

t₂​=$\frac{S/3}{2V}$

Time Taken in covering Third $\frac{1}{3}$​ distance of s,

t₃​=$\frac{S/3}{3V}$

Total time =t₁​+t_2​+t₃​= $\frac{S/3}{V}$+$\frac{S/3}{2V}$+$\frac{S/3}{3V}$​=$\frac{11S}{18V}$

∴ Average velocity=$\frac{Total dis\tan ce}{Time taken}$=$\frac{S}{{\displaystyle \frac{11S}{18V}}}$​= ​$\frac{18V}{11}$