The current of a stream runs at the rate of 4 kmph. A boat goes 12 km and back to the starting point in 2 hours, then find the speed of the boat in still water?
Choose the correct choice from the following answers: A) A)17.33 B) B)2 C) C)18 D) D)16 E) E)13.21
S = 4   M = x   DS = x + 4   US = x - 4   12/(x + 4) + 12/(x - 4) = 2   x = 13.21   Answer:13.21
<result>E</result>
The current of a stream runs at the rate of 4 kmph. A boat goes 12 km and back to the starting point in 2 hours, then find the speed of the boat in still water?