8 litres are drawn from a cask full of wine and is then filled with water. This operation is performed three more times. The ratio of the quantity of wine now left in cask to that of the water is 16 : 65. How much wine the cask hold originally?
A) 18 litres B) 24 litres
C) 32 litres D) 42 litres
8 litres are drawn from a cask full of wine
Answer: B) 24 litres
Explanation:
Let the quantity of the wine in the cask originally be x litres
Then, quantity of wine left in cask after 4 operations =[x(1−8x)4]litres
∴[x(1−8x)4x] = 1681
⇒[1−8x]4=(23)4
⇒x=24
Subject: Alligation or Mixture – Quantitative Aptitude – Arithmetic Ability