If $A$ and $B$ are in the ratio $4:5$ and the difference of their squares is $81,$ what is the value of $A?$

$A$ sum of $Rs. 340.68$ is distributed among $L$,$M$,and $N$ such that $L$ gets $Rs. 5.72$ more than $N$ and $M$ gets $Rs. 2.24$ more than $L$. Find the amount $N$ gets (in $Rs.$).

$A$ certain sum of money was divided between $A$,$B$,and $C$ in the ratio $5: 6: 9$. If $A$ received ₹ $450$,what was the total sum divided?

In a college,$150$ students of $MBA$ are enrolled. The ratio of boys to girls is $7:8$. There are three disciplines in the college,namely,Marketing,$HR$,and Finance. In the Marketing discipline,there are $50\%$ girls of their total number and the boys are $40\%$ of their total number. In the $HR$ discipline,girls are $30\%$ of their total number while boys are $30\%$ of their total number. The Finance discipline has girls $20\%$ of their total number and the boys are $30\%$ of their total number. $7$ boys and $9$ girls are in the $HR$ and Marketing both. $6$ boys and $7$ girls are in the $HR$ and Finance both. $5$ boys and $8$ girls are in the Marketing and Finance both. $2$ boys and $3$ girls are enrolled in all the three disciplines. What percentage of students are enrolled in all three disciplines?

Annual income of Amit and Veer are in the ratio $3:2$,while the ratio of their expenditures is $5:3$. If at the end of the year each saves ₹ $1,000$,the annual income of Amit is (in ₹):

There is $1000 \, \text{litres}$ of milk in a pot. $100 \, \text{litres}$ of milk is taken out and the same amount of water is poured into it. Again, $200 \, \text{litres}$ of the mixture is taken out and the same amount of water is poured into it, and finally, $400 \, \text{litres}$ of the mixture is taken out and the same amount of water is poured into it. What is the amount of milk in the resulting mixture?