CAT (QA) PYQs

$A$ and $B$ are two railway stations $90 \mathrm{~km}$ apart. A train leaves $A$ at $9:00$ am, heading towards $B$ at a speed of $40 \mathrm{~km} / \mathrm{hr}$. Another train leaves $B$ at $10:30$ am, heading towards $A$ at a speed of $20 \mathrm{~km} / \mathrm{hr}$. The trains meet each other at

A man travels by a motor boat down a river to his office and back. With the speed of the river unchanged, if he doubles the speed of his motor boat, then his total travel time gets reduced by $75\%$. The ratio of the original speed of the motor boat to the speed of the river is

In a car race, car $A$ beats car $B$ by $45 \mathrm{~km}$, car $B$ beats car $C$ by $50$km, and car $A$ beats $C$ by $90 \mathrm{~km}$. the distance (in km) over which the race has been conducted is