$A$ dishonest milkman professes to sell his milk at cost price but he mixes it with water and thereby gains $25 \%$. The percentage of water in the mixture is?

$A$ person has a chemical costing $Rs. 25$ per $litre$. In what ratio should water be mixed in the chemical so that by selling the mixture at $Rs. 20$ per $litre$,he may get a profit of $25\%$?

$A$ bottle contains $81$ litres of pure milk. $\frac{1}{3}$ of the milk is replaced by the same amount of water. Again,$\frac{1}{3}$ of the mixture is replaced by the same amount of water. The ratio of the milk and water in the new mixture is

$A$ and $B$ are two alloys of gold and copper prepared by mixing metals in the ratio $5:3$ and $5:11,$ respectively. Equal quantities of these alloys are melted to form a third alloy $C.$ The ratio of gold and copper in the alloy $C$ is

In what ratio must a person mix three kinds of tea costing $Rs. 60$ per $kg$,$Rs. 75$ per $kg$,and $Rs. 100$ per $kg$ so that the resultant mixture when sold at $Rs. 96$ per $kg$ yields a profit of $20\%$?

In a zoo,there are rabbits and pigeons. If the heads are counted,there are $200$ and if legs are counted,there are $580$. How many pigeons are there?