A vessel is full of 80 litres milk. 8 litres milk taken out and replaced by water. Again 8 litre mixture taken out and replaced by water. Find the amount of milk in the final mixture so formed.

64.8 L

⇒ \(\frac{8}{80}\) = \(\frac{1⇒replaced}{10   ⇒total}\)

  =\(\frac{9⇒remaining}{10   ⇒Total}\)

             Milk:    Total        :       Remaining

1st process  :      10         :          9

2nd process :      10         :          9

                         100        :         81

ATQ,

100 R= 80 (given)

1R = \(\frac{4}{5}\)

Hence,

81R = 81 × \(\frac{4}{5}\) = 64.8 L

Alternate:

⇒ \(\frac{8}{80}\) = \(\frac{1⇒replaced}{10   ⇒total}\)

  =\(\frac{9⇒remaining}{10   ⇒Total}\)

Milk Remaining : 80 × \(\frac{9}{10}\) × \(\frac{9}{10}\) = 64.8L