In a mixture \(60 litres,\) the ratio of milk and water\( 2 : 1.\) If this ratio is to be \(1 : 2,\) then the quanity of water to be further added is:
Answer: A
Quantity of milk \(= (60 \times \frac{2}{3}) littres = 40 littres.\)
Quantity of water in it \(= (60 - 40) littres = 20 littres.\)
New ratio \(= 1:2\)
Let quantity of water to be added further be \(x \) \(littres.\)
Then, milk : water \(= (\frac{40}{20 + x})\)
Now, \((\frac{40}{20 + x}) = \frac{1}{2}\)
\(\Rightarrow 20 + x = 80\)
\(\Rightarrow x = 60.\)
\(\therefore\) Quantity of water to be added \(= 60\) \(littres.\)