The current of a stream at 1 kmph. A motor boat goes 35 km upstream and back to the starting point in 12 hours. The speed of the motor boat in still water is?
Choices: A) 6 kilometre per hour B) 8 kmph C) 9 kmph D) 10 kmph E) 3 kmph
S = 1   M = x   DS = x + 1   US = x - 1   35/(x + 1) + 35/ (x - 1) = 12   x = 6   6 kilometre per hournswer:6 kilometre per hour
<result>A</result>
The current of a stream at 1 kmph. A motor boat goes 35 km upstream and back to the starting point in 12 hours. The speed of the motor boat in still water is?