A boat travelling downstream travels 16 kilometres in two hours, but a boat travelling upstream travels the same distance in four hours. In calm water, what is the boat's speed?
A. 4km/hr
B. 6 km/hr
C. 8 km/hr
D. Data inadequate
Answer:B
A boat travelling downstream travels 16 kilometres in two hours, but a boat travelling upstream travels the same distance in four hours. In calm water, what is the boat's speed?
A. 4km/hr B. 6 km/hr C. 8 km/hr D. Data inadequate
Explanation: Downstream rate = 16/2 kmph = 8 kmph,Upstream rate = 16/4 kmph = 4 kmph,In calm water, 1/2 (8 + 4) kmph equals 6 kmph.