Walking at $3 \, km/h$,Pintu reaches his school $5 \, minutes$ late. If he walks at $4 \, km/h$,he will be $5 \, minutes$ early. The distance of Pintu's school from his house is (in $km$):

Two guns were fired from the same place at an interval of $13 \text{ minutes}$,but a person in a train approaching the place hears the second shot $12 \text{ minutes } 30 \text{ seconds}$ after the first. Find the speed of the train,assuming that sound travels at $330 \text{ m/s}$ (in $\text{km/hr}$).

With a uniform speed,a car covers a certain distance in $8 \, hours$. Had the speed been increased by $4 \, km/hr$,the same distance could have been covered in $7.5 \, hours$. What is the distance covered? (in $km$)

Car $A$ runs at the speed of $65 \text{ km/h}$ and reaches its destination in $8 \text{ hours}$. Car $B$ runs at the speed of $70 \text{ km/h}$ and reaches its destination in $4 \text{ hours}$. What is the respective ratio of distances covered by Car $A$ and Car $B$?

In a flight of $600 \, km$,an aircraft was slowed down due to bad weather. Its average speed for the trip was reduced by $200 \, km/hr$ and the time of flight increased by $30 \, minutes$. The duration of the flight is (in $hour$):

$A$ train crosses a pole in $10 \, s$ and a platform,which is $40 \%$ longer than the length of the train,in $24 \, s$. If the length of the platform is $140 \, m$,what is the speed of the train in $m/s$?