The speed of a boat in still water is 24 km/hr and the rate of current is 3 km/hr. The distance travelled downstream in 15 minutes is
Select the correct option.
A) 1.6 km
B) 2 km
C) 3.6 km
D) 6.75 km
E) none of these

Rationale: "explanation : speed downstreams = ( 24 + 3 ) kmph = 27 kmph . distance travelled = ( 27 x 15 / 60 ) km = 6.75 km option d"
Answer: D