Marks of $X$ and $Y$ are in the ratio $3: 11$ respectively. If the marks of $X$ are $9$,then find the marks of $Y$.

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: 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 $HR$ and Marketing both. $6$ boys and $7$ girls are in $HR$ and Finance both. $5$ boys and $8$ girls are in Marketing and Finance both. $2$ boys and $3$ girls are enrolled in all the three disciplines. By what percent is the number of boys in the Marketing discipline more than the number of girls in the $HR$ discipline?

$A$ box contains ₹ $56$ in the form of coins of one-rupee,$50-paise$ and $25-paise$. The number of $50-paise$ coins is double the number of $25-paise$ coins and four times the number of one-rupee coins. How many $50-paise$ coins are there in the box?

An alloy of copper and zinc is taken in the ratio $1: 2$,and another alloy of the same metals is taken in the ratio of $2: 3$. How many parts of the two alloys must be taken to obtain a new alloy consisting of copper and zinc that are in the ratio $3: 5$?

Three vessels having volumes in the ratio of $2: 3: 5$ are full of a mixture of water and milk. In the first vessel,the ratio of water and milk is $1: 3$,in the second $2: 3$,and in the third vessel,$2: 5$. If all the three vessels are poured into a large container,what is the resulting ratio of milk and water?

₹ $120$ is divided among $6$ men, $8$ women and $6$ boys so that a man gets as much as $2$ boys and $2$ women get as much as $3$ boys. Find the share of a boy (in ₹).