Two tanks A and B. A fills 1 ltr/1 hr... b fills 10, 20, 30..... per hour. if this is (passage unnecessary). if 1/4th tank of b takes 15 hrs to fill how much it time will t take to fill complete tank?

• 1/4 -> 15hr;
  1/2 ->16hr
  1 ->17hr
  so ans = 17hrs
• 12 years agoHelpfull: Yes(7) No(23)
• first see "B" fills tank in 10,20,30...order not in 10,20,40,80....
  so time required for "B" pipe to fill 1/4th tank is 15hrs.
  that is 1/4=0.25 so to fill it completely it requires 4*15=60hrs (as 0.25 is 1/4 part of total tank)
• 11 years agoHelpfull: Yes(6) No(9)
• 1/4thin 15hrs
  1/2 in 16 hrs
  and ans is 17 hours
• 12 years agoHelpfull: Yes(2) No(15)
• assuming the rate of filling of B is an AP i.e it increases by 10 every hour.
  In 15 hours volume of water in the tank B=10+20+30...150=1200
  
  total capacity of B =4x1200=4800lts
  
  we need the some of the ap to become 4800 so
  
  4800=n(2a+(n-1)d)/2 sum of ap to n terms
  
  ans comes 30.48 hrs
• 11 years agoHelpfull: Yes(2) No(1)
• SHORTCUT:
  1/4 can be represented in the powers of 2 as 2^2.
  Time taken is 15hrs...
  hence, 15+2= 17 hrs.... :)
• 11 years agoHelpfull: Yes(2) No(1)
• in 1/4, 4 can be written as 2^2...
  so now add the power 2 i.e 2 to 15 ie15+2=17
• 12 years agoHelpfull: Yes(1) No(14)