The speed of a boat in still water is 12kmph and the rate of the current is 6kmph. The distance travelled downstream in 45 minutes is:

 a) 7 km
 b) 4.5 km
 c) 13.5 km
 d) 9 km

13.5 km. Solution Speed downstream = 12 + 6 = 18kmph Time = 45 min = 3/4 hours Distance = speed x time = 18 x 3/4 = 13.5km