The ratio of the number of boys to girls in an institution is $6:5$. If there are $192$ boys in total,find the total number of students in the institution.

If $4 \, \text{years}$ ago the ratio between the ages of $P$ and $Q$ was $5:6$ and the sum of their ages at present is $52 \, \text{years}$, what is the ratio of their present ages?

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 ₹):

$A$ man spends $Rs. 2310$ on an average during the first $8$ months from his income. During the next $4$ months,he spends $Rs. 1800$ on an average from his income,but he had taken a loan of $Rs. 1680$ apart from his income to meet his expenses. If he spent all that he had,what is the ratio of his average income to his average expenditure?

Gold is $19$ times as heavy as water and copper is $9$ times as heavy as water. In what ratio should these be mixed to get an alloy $15$ times as heavy as water?

The sum of two numbers is equal to $25$ and their difference is $20$. The ratio of the two numbers is