$A$ sum of $Rs. 41$ was divided among $50$ children. Each boy gets $90$ paise and each girl $65$ paise. The number of boys is?

The ratio of alcohol and water in $40$ $litres$ of mixture is $5:3$. Then $8$ $litres$ of the mixture is removed and replaced with water. Now,the ratio of the alcohol and water in the resultant mixture is

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 $litres$)

$A$ milk vendor has $2$ cans of milk. The first contains $25\%$ water and the rest milk. The second contains $50\%$ water. How much milk should he mix from each of the containers so as to get $12$ litres of milk such that the ratio of water to milk is $3:5$?

$A$ vessel of $160 \text{ litres}$ is filled with milk and water. $70 \%$ of milk and $30 \%$ of water is taken out of the vessel. After this task,it is found that the vessel is now filled by $55 \%$ of its original total quantity. What is the original quantity of milk and water in the vessel respectively?

How much water must be added to a vessel which contains $80$ litres of milk at a cost price of ₹ $3.5/litre$ so that the cost of the milk reduces to ₹ $2/litre$? (in litres)