1) Without stoppage a train travels certain distance with an average speed of 80 km/h and with stoppages, it covers the same distance with an average speed of 60 km/h. How many min per the train stops ? A) 10 min B) 12 min C) 15 min D) 20 min E) 30 min Answer: Option CExplanation:Distance is constant Stoppage (time/h) = $\frac{Change\quad in\quad speed }{Faster\quad Speed}$ $=\frac{(80-60)}{80}$ $=\frac{1}{4}$ = 15 min
