The ratio of two numbers is $3:4$ and their sum is $420$. The greater of the two numbers is

Two candles of the same height are lighted at the same time. The first is consumed in $8 \text{ hours}$ and the second in $6 \text{ hours}$. Assuming that each candle burns at a constant rate,in how many hours after being lighted,the ratio between the height of the first and second candles becomes $2:1$?

If $A: B = 2: 3$ and $B: C = 3: 7,$ then $A + B : B + C : C + A$ is

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 $50\%$ of the total girls and $40\%$ of the total boys. In the $HR$ discipline,there are $30\%$ of the total girls and $30\%$ of the total boys. In the Finance discipline,there are $20\%$ of the total girls and $30\%$ of the total boys. $7$ boys and $9$ girls are in both $HR$ and Marketing. $6$ boys and $7$ girls are in both $HR$ and Finance. $5$ boys and $8$ girls are in both Marketing and Finance. $2$ boys and $3$ girls are enrolled in all three disciplines. What is the ratio of boys to girls only in the Marketing discipline?

How many one-rupee coins,$50$-paise coins,and $25$-paise coins,whose numbers are in the ratio $5:7:12$,are together worth $₹ 115$?

The monthly salaries of $A, B$ and $C$ are in the ratio $2: 3: 5$. If $C$'s monthly salary is $Rs. 12000$ more than that of $A$,then $B$'s annual salary is (in $Rs.$):