A boat running downstream covers a distance of 16 km in 2 hours while for covering the same distance upstream, it takes 4 hours. What is the speed of the boat in still water?

A)4 km/hr
B)6 km/hr
C)8 km/hr
D)Data inadequate

• Let speed of boat in still is =x km/Hr,speed of current=y Km/hr
  for down stream=x+y,Up stream=x-y
  16/x+y=2----(1)
  16/x-y=4----(2)
  after solving this eqn x=6km/hr,y=2km/hr
• 13 years agoHelpfull: Yes(8) No(2)
• Rate of downnstream=16/2=8km/hr
  Rate of upstream=16/4=4km/hr
  speed in still water=(8+4)/2=6km/hr
  
• 13 years agoHelpfull: Yes(7) No(1)
• downstream speed = 16/2 = 8
  upstream = 16/4 = 4
• 13 years agoHelpfull: Yes(4) No(1)
• ans b. 6km/hr.
  let speed of boat be x and that of stream be y. speed in downstream=x+y, speed in upstream=x-y. according to question. 2(x+y)=16 and 4(x-y)=16. solving this we get x=6,y=2. hence speed of boat in still water=6km/hr.
• 13 years agoHelpfull: Yes(4) No(0)
• Option B
  
  Explanation:
  
  Rate downstream =16/2 kmph = 8 kmph.
  Rate upstream = 16/4 kmph = 4 kmph.
  Speed in still water = (1/2)(8 + 4) kmph = 6 kmph.
  
• 11 years agoHelpfull: Yes(2) No(1)