$A$ merchant has $1000 \ kg$ of sugar,part of which he sells at $8 \%$ profit and the rest at $18 \%$ profit. If he gains $14 \%$ on the whole,then the quantity sold at $18 \%$ profit is.......$kg$.

If $2 \, kg$ of metal,of which $\frac{1}{3}$ is zinc and the rest is copper,is mixed with $3 \, kg$ of metal,of which $\frac{1}{4}$ is zinc and the rest is copper,what is the ratio of zinc to copper in the mixture?

$A$ mixture of milk and water measures $60 \, ltr$. It contains $20 \%$ water. How many litres of water should be added to it so that water may be $25 \% $ (in $ltr$)?

Three boxes of capacity $24\, kg$,$36\, kg$,and $84\, kg$ are completely filled with three varieties of wheat $A$,$B$,and $C$ respectively. All three boxes were emptied,the three types of wheat were thoroughly mixed,and the mixture was put back into the three boxes. How many $kg$ of type $A$ wheat would be there in the third box?

$A$ shopkeeper bought $15 \text{ kg}$ of rice at the rate of $Rs. 29$ per $\text{kg}$ and $25 \text{ kg}$ of rice at the rate of $Rs. 20$ per $\text{kg}$. He sold the mixture of both types of rice at the rate of $Rs. 27$ per $\text{kg}$. His profit in this transaction is (in $Rs.$)

Gold is $19$ times as heavy as water and copper is $9$ times as heavy as water. In what ratio should these metals be mixed so that the mixture may be $15$ times as heavy as water?