$A$ train $150 \, m$ long takes $20 \, s$ to cross a platform $450 \, m$ long. The speed of the train in $km/h$ is:

Two trains start from $P$ and $Q$ respectively and travel towards each other at a speed of $50\, km/hr$ and $40\, km/hr$ respectively. By the time they meet,the first train has travelled $100\, km$ more than the second. The distance between $P$ and $Q$ is (in $km$):

The train fare between Patna and Munger for one adult is three times the train fare of one child. If the adult fare is $102$,what will be the total fare for $2$ adults and $3$ children for the same distance?

Heena and Renu are competing in a $100\, m$ race. Initially,Heena runs at twice the speed of Renu for the first $50\, m$. After the $50\, m$ mark,Heena runs at $\frac{1}{4}$ of her initial speed,while Renu continues to run at her original speed. If Renu catches up with Heena at a distance of $N$ meters from the finish line,then $N$ is equal to (in meters).

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:

$A$ farmer travelled a distance of $61 \, km$ in $9 \, hours$. He travelled partly on foot at $4 \, km/h$ and partly on bicycle at $9 \, km/h$. The distance travelled on foot is (in $km$)