one pipe fills d tank in 3hrs & another pipe empty d tank in hrs4.30.how much time required to fill d tank if both pipes working at a time

• as one pipe can be filled in 3 hrs,1/3rd part of tank can be filled
  the other pipe as it takes 41/2 hrs to empty,9/2rd part gets empty....when both work at a time, so 1/3-2/9=1/9
  hence it takes 9 hrs to fill d tank....
• 12 years agoHelpfull: Yes(1) No(1)
• assume that water can be fill in tank is = 9 unit(LCM off 3 and 4.5)
  water fills per hour is = 3 unit
  water empty per hour is = 2 unit
  resultant water per hour= 1 unit
  to fill total 9 unit time= 9 hours
• 12 years agoHelpfull: Yes(1) No(1)
• 9 hrs
  if both work parellel then the tank fill in one hrs=1/9
  so tank fill in 9 hrs
• 12 years agoHelpfull: Yes(0) No(1)