$A$ boy goes to his school from his house at a speed of $3 \, km/hr$ and returns at a speed of $2 \, km/hr$. If he takes $5 \, hours$ in total for the round trip,the distance between his house and school is (in $km$):

Aditya rides a cycle at the speed of $15\, km/h$ but stops for $10\, minutes$ to take rest every $20\, km$. How much time will he take to cover a distance of $150\, km$?

$A$ man walks a certain distance and rides back in $4 \, h \, 30 \, min$. He could ride both ways in $3 \, h$. The time required by the man to walk both ways is?

Excluding stoppages, the speed of a bus is $54 \, km/h$ and including stoppages, it is $45 \, km/h$. For how many minutes does the bus stop per hour?

Two places $P$ and $Q$ are $162 \, km$ apart. $A$ train leaves $P$ for $Q$ and simultaneously another train leaves $Q$ for $P$. They meet at the end of $6 \, hours$. If the former train travels $8 \, km/h$ faster than the other,then the speed of the train from $Q$ is (in $km/h$):

$A$ train $300 \ m$ long is running with a speed of $54 \ km/h$. In what time will it cross a telephone pole? (in $seconds$)