Question 25

# A jar contains a mixture of 175 ml water and 700 ml alcohol. Gopal takes out 10% of the mixture and substitutes it by water of the same amount. The process is repeated once again. The percentage of water in the mixture is now

Solution

Final quantity of alcohol in the mixture = $$\dfrac{700}{700+175}*(\dfrac{90}{100})^2*[700+175]$$ = 567 ml

Therefore, final quantity of water in the mixture = 875 - 567 = 308 ml

Hence, we can say that the percentage of water in the mixture = $$\dfrac{308}{875}\times 100$$ = 35.2 %