Pure milk costs $16 / L$. After adding water,the milkman sells the mixture at $15 / L$ and thereby makes a profit of $25 \%$. In what respective ratio does he mix milk with water?

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?

Nikita bought $30 \text{ kg}$ of wheat at the rate of $Rs. 9.50$ per $\text{kg}$ and $40 \text{ kg}$ of wheat at the rate of $Rs. 8.50$ per $\text{kg}$ and mixed them. She sold the mixture at the rate of $Rs. 8.90$ per $\text{kg}$. Her total profit or loss in the transaction was:

Nine litres of water are drawn from a container full of water and it is then filled with milk. Nine litres of mixture are drawn and the container is again filled with milk. The ratio of the quantity of water now left in the container to that of the milk in it is $16:9$. How much liquid does the container hold? (in $litres$)

$A$ 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 $Rs.$)

$A$ shopkeeper bought $30 \text{ kg}$ of rice at the rate of $₹ 70$ per $\text{kg}$ and $20 \text{ kg}$ of rice at the rate of $₹ 70.75$ per $\text{kg}$. If he mixed the two brands of rice and sold the mixture at $₹ 80.50$ per $\text{kg}$,his total gain is (in $₹$):