In one hour,a boat goes 11 km along the stream and 5 km against the stream.The speed of the boat in still water (in km/hr) is :	Choose the correct option.
A) 3 B) 5 C) 8 D) 9 E) 10

Rationale: "solution speed in still water = 1 / 2 ( 11 + 5 ) kmph . = 8 kmph . answer c"
Answer: C