If both the pipes are opened, how many hours will be taken to fill the tank?
I.The capacity of the tank is 400 litres.
II.The pipe A fills the tank in 4 hours.
III.The pipe B fills the tank in 6 hours.

A. Only I and II
B. Only II and III
C. All I, II and III
D. Any two of the three
E. Even with all the three statements, answer cannot be given.

• B is the correct answer
  The pipe A fills the tank in 4 hours and the pipe B fills the tank in 6 hours.
  so total tank filled in 1 hour by using two = 1/6 + 1/4 = 5/12
  so time required to fill the tank = 12/5 hours
  I statement is not required
• 13 years agoHelpfull: Yes(17) No(5)
• Only II and III
  
  option:B
  
• 13 years agoHelpfull: Yes(4) No(2)
• 2nd and 3rd statemnts are enough to calculate the time required to fill the tank i.e..,12/5 hrs
  
• 12 years agoHelpfull: Yes(3) No(2)
• the capacity cannot tell the amount filled in 1 hour although a's 1 hr contribution is given or b's. so 1 is invalid.
  b is the ans .
• 11 years agoHelpfull: Yes(0) No(0)