$A$ man goes from a place $A$ to $B$ at a speed of $12 \, km/hr$ and returns from $B$ to $A$ at a speed of $18 \, km/hr$. The average speed for the whole journey is (in $km/hr$):

Amit starts his journey from Patna to Delhi at a speed of $50 \, km/h$. The distance between Delhi and Patna is $1000 \, km$. He takes a rest of $20 \, minutes$ after every $3 \, hours$ of driving. How much total time will he take to reach Delhi? (in $hrs$)

$A$ train running at $\frac{7}{11}$ of its normal speed reached a place in $22\, \text{hours}$. How much time could be saved if the train had run at its normal speed? (in $\text{hours}$)

On a tour,a man travels at the rate of $64 \text{ km/h}$ for the first $160 \text{ km}$,then travels the next $160 \text{ km}$ at the rate of $80 \text{ km/h}$. The average speed in $\text{km/h}$ for the first $320 \text{ km}$ of the tour is:

Ramesh crosses a $600 \, m$ long street in $5 \, \text{minutes}$. His speed in $km/h$ is:

Two trains,each of length $125 \, m$,are running on parallel tracks in opposite directions. One train is running at a speed of $65 \, km/h$ and they cross each other in $6 \, s$. The speed of the other train is (in $km/h$):