The average speed of a bus is one-third of the speed of a train. The train covers 1125 km in 15 hours. How much distance will the bus cover in 36 minutes ?

Answer: Option E

Speed of the train :
$$\begin{array}{rl}& =\left(\frac{1125}{15}\right)\text{ km/hr}\\ & =75\text{ km/hr}\end{array}$$
Speed of the bus :
$$\begin{array}{rl}& =\left(\frac{1}{3}\times 75\right)\text{ km/hr}\\ & =25\text{ km/hr}\end{array}$$
Distance covered by the bus in 60 min = 25 km
Distance covered by the bus in 36 min :
$$\begin{array}{rl}& =\left(\frac{25}{60}\times 36\right)\text{ km}\\ & =15\text{ km}\end{array}$$