$A$ person crosses a $600\, m$ long street in $5\, minutes$. What is his speed in $km/hr$?

$A$ man takes $6\, h \, 15\, min$ in walking a distance and riding back to the starting place. He could walk both ways in $7\, h \, 45\, min$. The time taken by him to ride both ways is:

Two trains are running in opposite directions with speeds of $62 \, km/h$ and $40 \, km/h$,respectively. If the length of one train is $250 \, m$ and they cross each other in $18 \, seconds$,then the length of the other train is (in $m$):

Two cars $P$ and $Q$ start at the same time from $A$ and $B$ which are $120 \, km$ apart. If the two cars travel in opposite directions,they meet after $1 \, hour$,and if they travel in the same direction (from $A$ towards $B$),then $P$ meets $Q$ after $6 \, hours$. What is the speed of car $P$ (in $km/hr$)?

It takes $24 \, s$ for a train travelling at $93 \, km/h$ to cross entirely another train half its length travelling in the opposite direction at $51 \, km/h$. It passes a bridge in $66 \, s$. What is the length of the bridge in meters?

If a train runs at $40 \text{ km/h}$,it reaches its destination late by $11 \text{ minutes}$,but if it runs at $50 \text{ km/h}$,it is late by $5 \text{ minutes}$ only. Find the correct time for the train to complete its journey (in minutes).