A thief steals a car at 2.30 pm and drives it at 60 kmph. The theft is discovered at 3 pm and the owner sets off in another car at 75 kmph. When will he overtake the thief ?

Suppose the thief is overtaken x hrs after 2.30 pm
The, distance covered by the thief in x hrs = Distance covered by owner in $$\left( {x - \frac{1}{2}} \right)$$  hrs
$$\eqalign{ & \therefore 60x = 75\left( {x - \frac{1}{2}} \right) \cr & \Leftrightarrow 15x = \frac{{75}}{2} \cr & \Leftrightarrow x = \frac{5}{2}{\text{ hrs}} \cr} $$
So, the theif is overtaken at 5 pm