There are $65$ students in a class. $39$ rupees are distributed among them so that each boy gets $80$ Paise and each girl gets $30$ Paise. Find the number of boys and girls in that class.

$A$ can contains a mixture of two liquids $A$ and $B$ in the ratio $7:5$. When $9$ litres of the mixture are drawn off and the can is filled with $B$,the ratio of $A$ and $B$ becomes $7:9$. The quantity of liquid $A$ contained by the can initially was:

Two casks of $48$ $litres$ and $42$ $litres$ are filled with mixtures of wine and water,the proportions in the two casks being respectively $13:7$ and $18:17$. If the contents of the two casks are mixed,and $20$ $litres$ of water is added to the whole,what will be the proportion of wine to water in the resultant mixture?

$A$ $20\, \text{litre}$ mixture of milk and water contains milk and water in the ratio $3:2$. $10\, \text{litres}$ of the mixture is removed and replaced with pure milk,and the operation is repeated once more. At the end of the two removals and replacements,what is the ratio of milk and water in the resultant mixture?

$A$ drum contains $80$ $litres$ of ethanol. $20$ $litres$ of this liquid is removed and replaced with water. $20$ $litres$ of this mixture is again removed and replaced with water. How much water (in $litres$) is present in this drum now?

Aditya,Sonal,and Nutan contributed $Rs. 50,000$ for a business. Aditya contributed $Rs. 4,000$ more than Sonal,and Sonal contributed $Rs. 5,000$ more than Nutan. Out of a total profit of $Rs. 70,000$,how much did Aditya receive? (in $Rs.$)