In a mixture of $25\, L$,the ratio of acid to water is $4: 1$. Another $3\, L$ of water is added to the mixture. The ratio of acid to water in the new mixture is

Two vessels contain milk and water in the ratio $3:2$ and $7:3$. Find the ratio in which the contents of the two vessels have to be mixed to get a new mixture in which the ratio of milk and water is $2:1$.

$A$ man has $40 \ kg$ of tea,a part of which he sells at $5 \%$ loss and the rest at the cost price. In this business,he incurs a total loss of $3 \%$. Find the quantity of tea which he sells at the cost price (in $kg$).

$50 \, g$ of an alloy of gold and silver contains $80 \%$ gold (by weight). The quantity of gold,that is to be mixed with this alloy,so that it may contain $95 \%$ gold,is (in $g$)

$A$ mixture contains wine and water in the ratio $3:2$ and another mixture contains them in the ratio $4:5$. How many litres of the latter must be mixed with $3 \, L$ of the former so that the resulting mixture may contain equal quantities of the wine and water? (in $L$)

$A$ mixture of $48$ litre of milk and water contains $10 \%$ of water. How much water must be added to make $20 \%$ water in the new mixture?