4L are drawn from a cask full of wine ans is then filled with water. this operation is performed three more times. the ratio of the qty of wine now left in cask to that of water is 16:65.how much wine did the cask hold originally ?
a. 24L b.12L c.6L d.8L

• let the quantity of wine in the cask originally be x litres.
  then the quantity of water left in cask after 4 operations = x(1-4/x)^4 litres.
  [x(1-4/x)^4]/x = 16/81
  x =12 ans.
  
• 8 years agoHelpfull: Yes(0) No(0)
• but how this (1-4/x)^4
  plz xplain
• 8 years agoHelpfull: Yes(0) No(0)