When $x$ is added to each term of $7: 13$,the ratio becomes $2: 3$. The value of $x$ is

Find two numbers such that their mean proportion is $10$ and their third proportion is $1024$.

$94$ is divided into two parts in such a way that the fifth part of the first and the eighth part of the second are in the ratio $3:4$. The first part is:

$A, B$ and $C$ received an amount of ₹ $8400$ and distributed it among themselves in the ratio of $6: 8: 7$ respectively. If they save in the ratio of $3: 2: 4$ respectively and $B$ saves ₹ $400$,then what is the ratio of the expenditures of $A, B$ and $C$ respectively?

The difference between the ages of Meena and Seema is $3 \ yr$ and the ratio between their ages is $7: 8$. What is the sum of their ages (in $yr$)?

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?